DivIDE -as the name suggest- is an IDE interface originated from the Czech Republic. So far this is the only device in the 'new age', which became some kind of de facto standard interface internationally.

Before getting know about the interface, let's begin with its pre-history.

The ZX-IDE interface is the joint development of Lubomir Blaha (Tritolsoft) and Pavel Riha (PVL) from 1999. This one is an internal variant, which is also the first version of MB-HDFD built into the MB-02+.

For the authors, Matsoft brought the Pera Putnik's interface diagram downloaded from the Net. Its main problem was since the IDE HDD is a 16 bit device, and the Speccy is 8 bit, therefore the capacity of hard disk will automatically half of the nominal. So, the single I/O channel has been replaced to a six channel I/O structure. With this, and a special backup method, the full capacity can be used. The interface can handle two IDE devices (master and slave) at once.

The MB-02+ compatibility was solved by Dron. With the HDD_patch utility 2 megabytes of virtual disks are used. Later version of the program is also support LBA and DMA modes.

The next step is the external version of ZX-IDE interface prototype, which was never released to public. Busy has also helped in its implementation in optimizing of reading and writing operations. 64K EPROM, 128K battery backed SRAM and an NMI button were the main new features.

In 2002 February released the wired prototype of DivIDE 42r2 from Zilog (Pavel Cimbal). This was mainly based on the ZX-IDE interface, but returned to Pera Putnik's more primitive read-write operations. Contained 8K ROM and 32K RAM memory. Pavel's next and final prototype was DivIDE 42r4.

The first public version was DivIDE 57, mostly spread among the Czech colleagues from August 2002.

This was followed by DivIDE 57b, in which the IDE connector and NMI button was moved to a better position.

The most widespread model, DivIDE 57c is the same, but on the board the jumpers are signed with different characters.

In 2007 was released the R"GAL modification. The new chip is also even replaceable with the old R_GAL one. It can control two custom ROMs, which are paged into the Speccy's original ROM.

In order to eliminate the shortcomings of original DivIDE, the Polish Jarek Adamski and Jurek Dudek constructed the DiwIDE interface.

Although the original developers of the card were upset, they agreed in the fact, that DivIDE needs further improvements. Mainly it was necessary to enlarge the memory to fit inside the more complex operating systems.

DiwIDE v212 was the first public testversion. It was contain 32K EPROM, 128 or 512K battery backed SRAM. The CF connector was existed as only as an option, but the Sinclair thoroughgoing connector was already integrated by Jarek.

DiwIDE v317 or alternatively DivIDE Plus was the final release. Contains 512K ROM and 512K RAM onboard and has DivIDE and MB-02+ compatible modes. Also integrated a Compact Flash connector by default. The card incorporates six operating systems: the original FATware, ResiDOS, +DivIDE, DEFMIR, MDOS3 and TBIOS. In the future expected the support of CP/M and ZXVGS. Minimum exits in two subgenerations: as a green and a red coloured PCB.

The interface is sold by the English RWAP Software with DivIDE Plus name.

In the summer of 2012 was released the 3 chips GAL upgrade kit. This offers better compatibility, on the other hand, now it is possible to run the ESXDOS operating system, which was freezing so far.

Velesoft, DivIDE 512 contains 512K SRAM and 128K ROM. It works with SD card as default (by an IDE/SD adapter) Additionally, the whole stuff is boxed onto a neat black plastic case. Have two modes: a DivIDE compatible, and the 'allram' mode, which is similar to the R"GAL tuning. RAM also can be write-protected. For realization the original 28 pin chip-mounting have to be replaced with a 32 pin one. Noby also helped in its creation. Release date: 2008. July 09.

The Dutch Ben Versteeg also producing DivIDE 57c, can be ordered through his blog or E-Bay shop. The German Sintech are also selling this interface, as well the CF-IDE adapter. In smaller quantity, can be ordered from the Czech Noby also.

The Polish Lotharek also offers DivIDE clones. The first bunch from 2009 is red, the second series of 57c clone is purple from 2010. His own development is the DivIDE 2k11. This is fully compatible with 57c, but due to the CPLD, further expansions are possible. As it is a newer design, the card is also smaller size compared to the original.

Ewgeny7 used as a starting point the DivIDE 57c to develop the Russain-clone compatible MultiIDE version. This has already a ZX-Bus connector. The most important innovation is the Flash memory module, in which simultaneously 8 operating system can be placed in. Selection from them is done by jumpers. Who want to order, can do it through zst's homepage, he will send his usual blue coloured expansion card.

Victor Trucco is the DivIDE 57d series. Its three subversions: 57d, blue: for Brazilian users; 57d2, green: for the Czech colleagues; and the purple 57d3 for World of Spectrum forum members. The most important novelty is, that with jumpers can be switched to TK90 and 95 clone compatible. It also contains a signal booster, ZX and IDE reset. The HDD power plug was replaced with the IDE adapter power plug.

DivIDE is compatible with all ATA devices including HDDs, CDs/DVDs and CF cards (the last option is the most popular among the users).

Data transfer speed is 218K/sec and the full capacity of ATA devices useable. Compatible with all Spectrum variants and clones.

Updated: 2012. September 01.

Megadrive 256

Tnt23's (Tim Tashpulatov) SD card floppy emulator is named Megadrive 256. Amiga owners also know as Amiga Floppy Emulator. This is only partially covers the reality, as also compatible with ZX/TR-DOS, Atari ST, and MSX disks.

The prototype (…) was followed by the yellow coloured PCB Megadrive 128. Then the 'green' Megadrive 256 v1.0 and v1.1 was released.

The card could get fancy green, white or yellow coloured LCD, and floppy sound is simulated by a mini piezo speaker. The onboard memory is represented by an antique 4/8 megabytes SIMM module, here will be loaded the floppy image files from SD card.

It takes approximately 15-20 seconds, for the compresses formats (for example Atari ST) this time is increased by the unpacking time. In case of TR-DOS disks, this time is 16 seconds. We can navigate in the menus of alphanumerical display with five buttons.

About the mass storage devices: SD cards supporting the FAT32 file system, tnt23 tested maximum 2Gb ones (long file names and using of subdirectories are supported).

The IDE connector is 'officially not supported'. Although the designer tested it some old CF cards and HDDs, decided not to focus on IDE functions (therefore not ever card has the IDE connector soldered).

HcX Floppy Emulator

The idea of HxC Floppy Emulator appeared on early 2006. Jean-Francois Del Nero (jfdn, Jeff, HxC, HxC2001) as an Amiga and Atari ST fan would like to use his old machines, but without the old, annoying floppies. Then was born the first prototype of HxC, which is connected via the parallel port to a PC. On the 'another end of the line' was the 34 pin floppy connector of the Amiga or Atari. Between them the TTL-based converting device, the emulator card.

On 2006. December 08. saw the light the enhanced version, which is built around the Altera CPLD, and the parallel socket was changed to an USB 1.1 one. Hence its name is: USB HxC Floppy Emulator. The PCB is available in two versions: Rev B is a homebrew one, and Rev C is a professional, two-layer construction.

Among the classical micros, usable on ZX Spectrum +3/+2A/B computers. It handles the .DSK, extended .DSK format (read-only, special image file). The best thing is the support of .TRD and .SCL files, so new Russian programs will run on a traditional micro.

On 2007. April 05. was born the HxC Floppy Emulator SDCard FGPA-based prototype.

Then, on 2007. December 22., the SDCard HxC Floppy Emulator, built with the PIC18F MCU and alphanumerical display, which is Jean's last development. This supports SD cards up to 2Gb and SDHC cards up to 32Gb with about 500K/sec data transfer speed.

Using the FAT32 file system, support of long file names and subdirectory structure is also solved. Anyway, the same disk image formats are supported as in the case of USB version.

The professional quality version of this interface manufactured by the Polish Lotharek since 2010 March 13., which is made on his usual, red-coloured PCBs. It has detachable display, 3 LEDs and 3 buttons (next, back, eject) and a small speaker. Otherwise, the USB-version also can be ordered from him, and from several (independent) producers also distributing the USB-version.

ZXMMC és ZXMMC+

Alessandro Poppi, the author of ZX Badaloc clone has two another development: the ZXMMC and ZXMMC+ interfaces. Although only a "+" sign difference in the nomination, there are a lot of differences between the two cards: certainly the plus version is more complex.

The ZXMMC card can plugged into the Z80 socket of 128K+2A/B and +3 machines (Theoretically compatible with all Spectrums, but there is psychical problems in building in). It is connected to the development of ZX Badaloc clone and it is a SD/MMC card reader-writer. Transfer speed is 218KB/sec at 3.5MHz. Not only with the Spectrum, but compatible wit all Z80 based machines. The interface supports two cards, but there is only one port on the PCB. Who really want, can solder the second port onto the top of first. It has two subgenera: the basic version only capable to read and write. The full variant also contains Kempston joystick and RS-232C ports.

The ZXMMC+ is fairly extends the possibilities of the Spectrum. Above the extras of ZXMMC full version, it has 512K battery backed RAM and same size of Flash ROM. Got NMI and reset buttons and a thoroughgoing edge connector.

ZX Spectrum +3e is supporting these devices.

Interface 1Bis Version 4b

The 'M' drive can be a maximum 128Gb capacity SD card split into 32 megabyte partitions. Also there is a possibility to connect it to a PC through an USB port and we can use its shared drive as letter 'V'. No maximum size limit is here. These are the possibilities of handling of the .TAP, .Z80 and .SCR files.

On the card clearly visible the nearly two decades long development. Its main features the double layer PCB with CPLD, and the very robust, overbuilt finalization.

It also has Kempston Joystick and PS/2 mouse ports. The last can be Kempston mouse or Joystick compatible.

First version (Version 1a) saw the light in 1994. This was a expansible card with four fully buffered expansion slots.

The whole thing is placed into an Atari Gameselex box, and the card itself was made on an Apple II prototype card. Memory could be 32, 128 or 512K SRAM chips, accessible as maximum three 128K RAMdisk.

It had Centronics and Kempston Joystick ports. The operating system is burnt into the shadow ROM. It emulates the original Interface 1 (of course the previously mentioned ZX-Net and RS-232 excepted), and also contains a 32/64 column printer driver.

Interface 1Bis Version 1b

Version 1b was appeared four years later. The PIO mode IDE controller was built on a separate ISA XT prototype card. It was introduced the virtual 32 megabytes Microdrive support. Also it was the very first time realization of the client-server connection, of course using the parallel port for connecting the 'V' drive at this time.

In 2002 released an IDE controller for the Z80-based machines, which was crunched into a 36 macrocell CPLD - this was an intermediate step for the further development.

In 2004, with Version 2a, the interface was integrated into a 72 macrocell CPLD, which now was fit into a Multicomp MB3 box, while retaining its full functionality.

Between 2005 and 2008 (Version 2b-2e) was the period of memory optimization (shadow ROM, memory area and puffer).

In year 2009, in the case of Version 2f, five input and output lines replaced the grounding lines. So from this time we can speak about streaming parallel port, which works with 8 input and output, as well 4 control ports for the communication.

Again in 2009 saw the light the Parallel Port peripheral too. This is an MCU-based device, which is connected to the parallel port and gives RS-232, USB 2.0 and 12MHz SPI port support. In the same time, the drivers also written for the device.

After another one year, the support of SD card also realized by the previously mentioned SPI port. At the same time, the file system of SD and HDD was also improved.

Again, in the same year, another module was born, which named to System Bus peripheral. As its name suggests, directly connected to the system bus. Also an MCU-based device, and supports SD-card, USB, Kempston Joystick and Kempston Mouse (PS/2) ports.

Interface 1Bis Version 2i

Version 2g-i is the fruit of the same year, at this time the above mentioned module was improved.

The next variant from 2011 was Version 3a. At this time, the interface and the winchester together were integrated into a Dk'tronics house. Parallel port was eliminated. Meanwhile, the modern USB and micro-SD card ports integrated. At the same time, the size of the card became more and more compact and got a 'real' power supply instead of the dead Spectrum's power unit.

In 2012 in order to prepare the small number series production, the IDE port was cut off with Version 4a. So now the logic of the card was fitted into a 36 macrocell CPLD.

After a year, with Version 4b, the RAM drive option was also deleted. In that way, only 32K SRAM necessary for the card, and six I/O lines were freed up. The PCB got a voltage regulator circuit, which now measures 100x49,5 mm and it is two layered. The possibilities of the (small) series production now ready, first units were came out in January of 2013.

Z-Controller

Z-Controller is also King of Evil's inventment, the guy with the Pentagon 1024SL computer. This one is a really universal too: we can connect PS/2 keyboard and mouse, contains an IDE controller for hard disk and CD-ROM as well a Flash Card adapter.

Signals of PC keyboard are converted to standard Spectrum signals with some extras (for example F11: Magic Button, F12: reset). Signals of PS/2 mouse are converted to Kempston Mouse.

Anyway, the IDE controller is developed on the basis of Nemo's card. Empty circuit boards can be ordered for 300 rubles, and made in the Zelenograd factory such as the Pentagon 1024SL with today's standard. Those, who feel enough competent, with the free access documents can make one for themselves.

The developer was testing it on Pentagon 1024SL, Scorpion and certainly with KAY 1024 machines.

Pentagon 1024SL v2.666 already contains this extender integrated onto the mainboard, with some extras, such as USB and VGA ports, as well a real-time clock - as described earlier.

ZX Multi Card

ZX Multi Card is the inventment of the Russian Caro (real name: Kamil Karimov). With help of that device, quite well can enhance the possibilities of the Spectrum.

Through the card, we can attach PS/2 keyboard and mouse, and it is also contains a real time clock.

Signals of PS/2 mouse are automatically converted to Kempston Mouse signals. In addition, this multifunction card also contains a modem. These devices can be tested trough built-in programs with pressing Win, F1, F2 and F3 simultaneously.

With further module enhancements SD/MMC cards as well conventional tapes can be used as storage devices. An another extender contains a MIDI Out port.

Version1.x boards were followed by the v2.x ones, which have bugfixed board. Beside that, some ICs are integrated into a simple circuit.

Again, all documents are freely available.

ProfROM

The initial disgusting feature of Scorpion from other clones was the utilities burnt into the ROM. The so-called ’Service Monitor’ first only occupied 16K, but extending its functions, soon reached the 64K limit.

Further utilies (’Professional Extension’) wanted to be load externally from floppy disk, so programs would occupy a portion of RAM. But this would lead to compatibility issues.

That is the reason why Scorpion decided to construct Professional ROM (ProfROM, which is a mini ROM board in 128K and 256K versions. First one can hold 80K of programs, second is capable of 208K. A 512K variant is also exists, which divides the capacity into two 256K parts, we can select them by a switch.

ProfROM has some nice features: compatible with SMUC, able to configure mouse and joystick, fast formatting of floppies, as well contains screen editor and debugger.

ProfROM Second Edition is the design of Witchcraft Creative Group existing 128K or 256K versions. With a jumper not only to Scorpion, but can be connected to KAY and ZXM-Phoenix machines too.

Worth to note, that Velesoft already in 2007 designed his own version. It only exists on ’paper’ at the moment, not tested by even the author yet.

Added: 2010. January 23.

Proface AT

The weak point of Spectrum was the keyboard for a long time.

For solving this problem, quite wide range of devices were born. Still, you can buy interfaces with PC-keyboard connector. So, you don't have to afraid about the keyboard membranes, you can use the cheaper and better quality PC-keyboards.

Proface AT is existing in some versions. It has an internal and an external variant. Internal is suitable for people who want to build their Speccies into a PC-case. Of course, the internal is a bit cheaper too. Velesoft also engineered the PS/2 version.

Resets are going in the same way as on PCs: Ctrl+Alt+Del. Some floppy commands, such as Format, Cat are accessible through the function keys. Certainly, you can use the cursor keys and also the numeric pad. It has some another extra features, but most customers buy the interface only for connecting PC keyboards.

The external Proface also has a thoroughgoing edge connector. Good quality Speccy keyboard stickers are also come along with the interfaces. Sintech, RWAP Software and Kompakt Services are selling it.

IBM PC Keyboard and Mouse Contoller

Of course, Scorpion company also offers the possibility of connecting PC-keyboards.

Their joint development with D. K. (a firm also located in Saint Petersburg) is an universal XT/AT keyboard and mouse controller. It is compatible not only with Scorpion, but with another ZX Spectrum clones too.

The PC keyboard controller has some smart features. It detects XT/AT keyboards automatically. Also supports both Latin and Cyrillic keyboard layouts.

Common functions of most popular word processors (as TasWord, The Last Word 2, ZX Word) accessible directly from function keys. The same can be said from IS-DOS commands. Pressing Pause button will hang on running the programs, Ctrl+Alt+Del will reset the computer.

The mouse controller is converting the datas of Microsoft Mouse to Kempston mouse, make handling easier of new Russian software. But it also emulates classic Kempston, Cursor and Sinclair joysticks - even with autofire function.

Magic Button can be activated by keypress too.

Worth to note, that not all mouses and keyboards are compatible with the card. For that reason, better to buy it as a complete set (controller, keyboard and mouse). Russians also studying marketing...

The card is sold by Perspective Group too.

YAZSAKI

The initially in Great Britain grown up, presently living in the USA JROK offers an another solution for replacing the folie membrane of ZX Spectrum. The interface called Yet Another ZX Spectrum AT Keyboard Interface (YAZSAKI) and was born in 2006. The author was only wanted to play with Manic Miner, and see what is the result...

The fairly Japanese sounding interface only consists of two elements: the Xilinx XC9572 programmable logical circuit and the Amtel AVR Attiny45 micro-controller.

Of course, it supports the combined keypresses, so delete and cursor keys are useable among others.

The sample of printed circuit board, as well the driver software are downloadable from the website.

ZX Spectrum USB Keyboard Conversion

Lee and LanceR, two friends made an interface with ZX Spectrum USB Keyboard Conversion name.

So from that easy to guess, that it is an interface for attaching USB PC-keyboard for the Spectrum.

After solving the construction of the original folie-matrix, they modified an old 18f4550 card of LanceR. After it was worked fine, they replaced it with a more good-looking PCB.

Hozzáadva: 2011. October 22.

Probably most of you remember to the "poor man's soundcard" of early '90s - that was Covox. Some "scientific" names of the device: Covox Speech Thing or sometimes Covox Plug.

This is a simple digital to analogue converter attached to the parallel port. The signal can be boosted with hi-fi equipments, so both digitised effects and music can produced in quite good quality. Covoxes have some different versions beginning from IC variants to resistor type ones.

Covoxes had stereo and quadro versions also. First one is consist of two mono Covoxes, second is integrating four Covoxes into a small board (name of this device was Quadrofonic DAC).

Ready-made Covoxes were also commercially available named to Disney Sound Source. With decreasing the price of soundcards, Covoxes became less and less important - at least in the PC-world.

Among 8 bit home micros, Covox is widespread still (for example Atari XL, Spectrum, but the excellent products of Russian industry, Elektronika BK and Vector were also enhanced with Covox.). This was supposedly facilitated by the fact, that the AY-8910/12 and YM2148F sound chips did not have Russian analogues. Mono versions are existing, as well stereos. And Pentagon Covoxes a little different from the Scorpion's devices.

Quadro Covoxes named Soundrive (one "d!"). Just as at the PCs, four D/A converters integrated to a small board. First version was engineered by Flash Inc. from Novisibirsk in 1995. It has some different versions as Soundrive Normal, Soundrive Baby and Soundrive Monster. Covox and Soundrive were rather popular among users,who wanted to produce digital effects from the ZX Spectrum.

Versions are also become numerous such as 1.01., 1.02, 1.05, 1.50 and 1.51. Of course, Soundrive is Covox and Stereo Covox compatible.

Version 1.02 has 9 chips and in the Russian circumstances contained quite expensive and hardly obtainable elements.

Version 1.05 is made from cheaper and more widespread parts and can be made Covox compatible by a switch. Number of chips were reduced to 5.

Version 1.51 selects automatically Covox mode, if the program does not support Soundrive. Its schematics published in Flash Times diskzine in 1997.

Its modern age reincarnation is called Soundrive TLC7528C. This one is designed by solegstar in 2011, and it was announced on the zx.pk.ru forum as an usual habit with the new Russian devices. It is based on the TLC7258C dual channel D/A converter, from which needs two pieces. The card is ZX Bus compatible, Caro was helped in its creation. It also contains an AY-input to make possible the mixing. First, he made a prototype with PC Centronics plug. In theory, it is works with one piece TLC7225 DAC too, but the developer did not tested it yet. Fully compatible with 1.51 both on software and hardware levels and also with the Profi clone.

Covox and Soundrive's quality is 8 bit. In case of Covox the CPU must divide the signals in time-sharing system to the only port (1x8 bit) or at Stereo Covoxes to two ports (2x8 bit). Soundrive signals can directly ported to each channels (4x8 bit).

Russian games and sound softwares are using the different Covoxes. Greatest disadvantage of the devices, that producing music is completely done by the central processor.

Maximum quality is 10 kHz (with optimisation 12 kHz), if samples and volumes stored in high memory area. If the standard, low memory contains the music, then 15 kHz (or 16 kHz) could be reached.

Special Soundrive music editors: Digital Studio, Extreme Tracker, Flash Tracker, Ultrasonic and SQ Tracker.

Although in much less quantity, but in the territory of ex-Czechoslovakian Republic, Covox and Soundrive were also popular. These were home-made products since the end of 90's, official manufacturers or distributors did not existed.

Their common points, not connected directly to the machines, but through the UR-4 parallel port interface. Among others, Petr Simandl and Cygnus also published their circuit diagrams on their websites. Last one is on Bytefest 2007 party introduced for publicity the techically quite outdated, but surprisingly good quality converter with the ZN427 chip.

Czech/Slovakian Covoxes are made for playing three channel music, opposite of the Russian four channel devices.

Updated: 2012. May 19.

ABC/ACB/CAB sztereó

Stereo music is invented by the Czech Spec-chums, who soldered some condensers and resistors to the AY-chip and getting stereo music in this way. The tuning can be connected to Busy and Noro. This method was also popular in the territory of ex-Soviet Union and in smaller extents in Poland and in Romania too.

Although seems easy to make this modification, the AY-chip is very heat-sensible. So very easy to burn out the chip with soldering. Better to ask a more practised friend to realise this enhancement. Anyway your Spectrum will not music in stereo - in fact it will not music at all... Some DIY-sites are strongly recommending, not to heat directly the AY-chip, but better to soldering a separate chip socket.

ABC, ACB and CAB stereo modes referring to the orders of channel sequence. The AY-chip (as well the YM of course) has 3 different mono channels (A, B and C). These three channels are separated, and the channels marked with the two winger letters are sounding from the left and right speakers with full loudness. Centre channel is sounds from each speakers with half loudness. ACB stereo is the tuning of the Czech/Slovakian areas. ABC and BAC stereo was widespread in the territory of ex-Soviet Union.

The stereo sound not very difficult to take out to a hi-fi system, so not necessary to hear it from TV. By the way, AY-chip is capable to play digitised sound, although originally it is an undocumented feature. It is very CPU intensive task, and quailty does not reach 5 bit. Newer Russian games are fulfilled with digitised effects.

Stereo music is also becoming standard on most demo-compos.

For the 48K Speccies later appared the AY-chip interfaces, which had uncountable variants during the years. It has to modify a bit the 48K software to work properly with these enhancements -in that case, if they were not made to compatible originally. As before 1995 were not widespread the 128K machines in the ex-Czechoslovakian Republic, many games had been converted to 48K. Of course, our Czech friends tried to write 48K+AY compatible games.

At present, Melodik interface sold by Kompakt Services is the only one such commercial interface. It contains a built-in mono loudspeaker, but certainly can connected to the hi-fi equipment through a stereo 3,5 jack in ACB stereo.

Jarek Adamski's Yamod.AYLPT and Sami Vehmaa's ZXAY cards will described fully later.

Not belonging strictly to the topic, but worth to mention, that for some ex-Soviet clones was attached the stereo-tuned AY-chip through the bus system very similarly to the PC soundcards. The best example is the already mentioned Contact CPS-128. At the early Pentagons, into the socket of Z80 processor have to plug a small circuit which contained both the Z80 and AY chips - as we could read before.

AY-Magic

Zaxon's AY-Magic soundcard is the usual AY-interface for the ZX Spectrum. Fully compatible with the 128K Spectrum and beside its rubber-keyed mates and 48K+, also works fine with the clones. Theoretically, can be used with all variants of 128K, 128K+2 and 128K+3, but uses the same port, as the original chip, so it have not much sense (emulation of further described Turbo Sound will not work). Has a through connector and a jack socket.

According to the text in the PCB, Yerzmey also helped in its development.

Anyway, Zaxon also develops various interfaces for the C64 and Atari 8/16 bit machines.

Added: 2010. February 21.

Turbo AY/YM extensios

For those, who thought, the possibilities are ended with stereo-tuning and playing digitised effects with the AY/YM chips - they simple aren't right. The ancestor of 6 channel Turbo Sound (with two AY/YM chips) was existed in the SAM Coupe computer, although this task was integrated into a single Philips SAA1099 chip. Some sources from late 80's mentioned about similar developments for the original ZX Spectrum. Russians call this enhancement to Turbo Sound, Turbo AY or simply TS. Sources are speaking about it as the original development of Himik ZxZ, and later more anothers were further developed it.

Sadly nor each method compatible with others, except Velesoft's card. Let's see them step by step!

Pseudo-turbo mode is using the default port and a second AY-chip. The two chips are controlled by some phase-step delay from the same port.

Quadro-turbo (or Quadro-AY and in Russian: Kvadrapristavka) is a typical Pentagon modification: just put a second AY beside the original with different addressing port. Because one AY can sound in stereo, with two can produce quadro sound. This extended version saw the light in 1997 by Rush and Amazing Software Making. Unfortunately no programs are supporting this.

POS-turbo (from 1995) is the creation of the Power of Sound group. Previously they made the TR-DOS version 6.1x (more exactly they cracked it...), as it was written at the Beta-128 section. Their modification is also a second AY with different port. They developed different interfaces for the original Spectrum, Pentagon and Profi. Sound Power group released Turbo Sound Editor, other programs do not support this enhancement.

NedoPC-turbo sound similar to previous: a dual-AY with twin ports. With a micro-switch can be activated the second AY/YM chip. The name "Turbo" is very fits for in this case: this switch is very reminds us to the old 286's Turbo mode switch Executors of this sound enhancement are the designers of ATM Turbo 3 clone, the NedoPC group. It has more subgenerations such as Turbo Sound A, B, C and FM. C version already supports both normal/turbo speed machines as well old and new software. FM version is incorporates two YM2203 chips, and it is compatible with old AY and TS software and uses 12 channels. Unfortunately it is only compatible with normal speed Spectrums. As the chip is compatible with YM2612, so Sega MegaDrive and Genesis consoles' music can be played, and we can also compose Sega music on the Spectrum with the FM card! NedoPC is selling these enhancement in small series, but all technical documents are freely available for those who wants to assemble by themselves. On the various demo parties and another occasions, Turbo Sound cards were gifted as prizes, in order to facilitate the widespreading of the device.

VeleSoft also produced his own version. Turbo Sound Easy only contains one AY/YM chip (all other variants two). The card uses the computer's built-in chip as a primary music chip. Also has a Philips SAA1099 for emulating SAM Coupe sounds. So sound is 12 channels. Fully compatible with the NedoPC variant.

At the same time, 6 channel editors and players were appeared, for example Turbo Sound Player, Vortex Tracker II or a special version of Protracker. Even, on the newer demo compos there are separate Turbo Sound category (Chaos Constructions and Di'Halt).

Despite the facts, this enhancement is not so widespreaded, because you have to kill a Spectrum, Atari or Sega to get the necessary chip. And not so many programs supporting 6 channel music.

After all, varying the AY/AM chips' clock frequency can result in better sound quality (1,75MHz, 1,77MHz or 3,5MHz).

Now the first TS music "album" came out too - which is a 640K TR-DOS disk.

Good news for the developers: full documentation of Turbo Sound was released as a book from Alone Coder.

General Sound 128/512, NeoGS

Anyone can turn his Spectrum or Spectrum-clone into a nearly Amiga quality sound machine in seconds with the General Sound card (abbreviation: GS) - no matter it is a basic 48K or a more advanced 512K model.

This card is the development of X-Trade Group from 1997-98 (Saint Petersburg), but Scorpion and Nemo also engineered their own versions.

Thank to the complexity of board, home made or cloned GS cards not found on the market. To tell the true, this is the most difficult ZX Spectrum peripheral of the classical Russian ZX Spectrum era.

Certainly, most software does not use the extra capacities of the sound card. But most of newer Russian games, updated version of old classics, music editors and players are supporting it, some of them even autodetecting when the card plugged in.

In the case of old classic games, crackers are dug out the music and effects from the Amiga version, and simply attached them to the Speccy version. The soundcard excellent for editing and play back of Amiga originated .MOD files.

The hearth of GS is a Z80A, B, C or H running at 12MHz, with massive 128 or 512K DRAM. Fairly ironical an extension card, which is more powerful, than the computer itself...

Theoretically, as a coprocessor, can calculate everything independently from the computer's CPU. Even can share its memory with the ZX Spectrum. But this possibility is nearly unused in softwares.

Producing music is completely the task of the card's Z80 CPU, so it doesn't need serious resources from Speccy. When resetting the computer, GS will work further more.

Scorpion includes two disks along with the soundcard fulfilled with games and music.

If you see the GS128 or GS512 sign at a program, it means the support of General Sound card with 128 or 512K RAM.

Sampling rate is 37,5 KHz and has 4 different channels. Some of the sound editors with GS support: RIFF Tracker and Excellent Tracker.

NedoPC Group was developed the new version of General Sound card, which was introduced on June 2008 on DiHalt 2008 with NeoGS name. Fully compatible with the 512K General Sound card, and has some extended capabilities. In the development was participated LVD (Vadim Akim), CHRV (Chunin Roman), King of Evil (Zhabin Alexei) and JTN (Vasiliy Klimov).

Sales of first devices began at October 2008 and cost of ready-made board is 1.800 rubles, the DIY-kit is 1.500 rubles. At the current moment, have two revisions: Revision A, which never went to sale, and Revision B, the final version with error fixes.

And now the technical details: hearth of the board is a Z84 running either at 10, 12, 20 or 24MHz selectable, has 2 megabytes of RAM and 512K (Flash)ROM. Capable of playing .MP3 and 8 channel .MOD files, even from SD card. Built-in DMA circuit accelerates the data exchange. From the SD card, can play the files independently from the Spectrum, what means, powering off the computer does not influences NeoGS.

DMA Ultra Sound Card

DMA Ultra Sound Card (DMA USC) developed by Witch Craft Creative Group commonly with Aleksei Inozemtsevym in 1999. This Ukrainish novelty is a non-profit inventment, which never planned to push into serial production.

Its schematics are freely available. Thanks to the complexity of card (40 chips), difficulties in attaching to clones, as well to few programs using the possibilities of the it, it does not widespreaded too much. Nevertheless, it becomes fairly well-known due various publications of press and electronic magazines (MSD, Echo, Adventurer and Body). Unlike the more popular General Sound card, it does not have own memory, but using the computer's memory with direct memory access. With that method, opposite of Soundrive, CPU usage is only 15% when playing four-channel music. So theoretically 85 % left for games to run.

Attaching DMA USC card to clones needs high level skills. There are many different ZX Spectrum variants, that is why impossible to connect it without special knowledge. The user's guide deeply explains how to use the card with Pentagon 512K and KAY 1024K clones. From this seems, that recommended the card to attach for machines with minimum 512K memory. Another problem is, in turbo mode the card is unreliable. This could be solved only with a hardly available chip.

Developers of DMA USC adopted a number of music editors for this device. Some examples: Access Player, X-Tracker, Digital Studio, ProDigital Editor.

Miki RS232

Miki RS232 interface initially was the inventment of Busysoft. This one is connected through the UR4 interface, and offers standard RS-232C input/output. So it is basically a serial-parallel, parallel-serial converter interface. It is also possible to change data between the ZX and PCs. This circuit was realised with the AT89C2051 chip.

His compatriot, Cygnus also fabricated his own version, which is built around the AT Mega 16 chip. By his oppinion, its reason is more easy programming under Linux.

From the homepages, detailed informations as well some utilies are also available.

Sinclair Serial Interface

The Sinclair Serial Interface (Sinclair SIF) is the development of the Czech Pavel Urbancik. It has three main subversions, the newer ones offering backward compatibility with the oldies. Additionally, new functions were implemented and also got some error corrections comparing to older ones.

The hardware itself a dual channel serial interface, ready to open the door to the ‘real world’. First channel is an usual cabled RS-232C connection, ideal for example to connecting PCs. The another channel is an option to integrate a Wi-Fi or Ethernet component.

The possibilities are practically endless, ftp, text-based www or e-mail clients etc., but almost no software developed.

For 1.000 CSK or 40 Euros can be ordered without the Wi-Fi or Ethernet module.

Hozzáadva: 2009. december 22.

Pokeador Automatico

Fernando Fdez was published in 2005 the documents, which are necessary to rebuild the Pokeador Automatico interface as well the utilies, which are working with this hardware.

This one is a Spanish inventment, with which you can enter POKEs in the games as cheatings - presumably as the name suggests.

Reconstruction was prohibited by the fact, that documents were released in three different issues (Microhobby 117-118-119).

On the homepage, we can found the relevant three issues, the printed circuit board (which was redesigned by Fernando a bit) and the utilies. Original parts are also listed, and some recommendations to replace them with more common and cheap items.

SpeccyBoot

Patrick Persson successfully solved the booting of ZX Spectrum over on Ethernet network. The 'packet', which consist of hardware and software parts got the SpeccyBoot name.

This method was originally designed for diskless workstations for booting over a local network. SpeccyBoot is works in a similar way.

The machine gets an IP address over DHCP, then starts a file from the TFTP server (snapshots.lst), which is the list of the snapshots. Then from this list we can choose the right snapshot, we would like to run.

In case of Spectrum, pressing Caps Shift during the 'boot' loads the normal BASIC if the SpeccyBoot is connected.

The card is made with the MicroChip ENC28J60 Ethernet Controller. The author used the Olimex ENC28J60 -H development board, which is contains the previous chip. The price of SpeccyBoot is around 30 Euros with some another additional accessories in this case. If we do not use the whole development board, only the chip with its accessories, the final price is cut down to 15 Euros.

After building the hardware, needs to install the software. After compiling the source code, we get a .WAV file, which is need to load into the Spectrum (for example from a mobile phone). Then this program needs to burnt into the EEPROM.

The card is compatible with 48K/128K/128K+2 machines (maybe also with the 16K ones). Later Amstrad models have different layout edge connector, so without modification will not work (of course, this modification is possible, but Patrick did not have the opportunity to do this).

GMX

With Graphics Memory eXpander card easily "downgradeable" a Scorpion into a Pentagon. Any reasons for that? Well, yes, because the new age games and demos are mostly made for Pentagons, and they don't work properly on Scorps. GMX is soon became the favourite card of demoparties. It's because of faithful Pentagon emulation and it is more reliable and stable like the usually home-made Pentagons.

It emulates 4 another Speccy-variants, including Profi, from which inherited the memory mapping techniques between the 256K and 1M range (backward compatibility). Scorpion says, its reason is, that Profi 1024 is a relatively widespread clone with good software support – especially with end user applications. If we switch off every extra, we get back to the original Spectrum, except of the rubbers keys.

GMX gets some innovative features also. It has 2MByte of RAM, where can be loaded a lot of different things - for example ROMs in order to speed up your Scorp a bit. The card's CPU is a 3,5/7MHz Z80B, can be useful when playing Driller:) The 14MHz version was promised for years, but for now it is sure, nothing will happend with it. Difference between normal and turbo mode approximately is 1,8-1,9x; but with shadowing it is exactly will 2x faster. Some other possibilities of the card are including new graphics modes (for example 640x200) with standard Speccy colours. Also Multicolor capable. The new text mode offers 80x25 characters and can be displayed either on TV, CGA, EGA or VGA monitors.

The biggest problem with the GMX its price. It is equivalent with a complete Scorpion config - so an average user can only dreaming about it.

Kempston Mouse was originally the product of Kempston Micro Electronics Ltd. in 1986. It came along with a special version of Art Studio. As probably everybody knows, the company was famous from its joystick interfaces.

Comparing with its main rival, the AMX Mouse, it works fine with 128K Spectrums also, maybe because of it becomes the standard equipment of ex-Soviet clones. In Europe it never reached wide popularity, despite the fact, it was more superior quality than its rival with the same price, around 70 pounds. Although it went quite popular in the ex-Czechslovakian Republic beside the ex-Soviet Union.

The Russian version was developed independently by two different Spectrum owners nearly at the same time at Saint Petersburg: Maxim Romanov (RML/Create Soft) and Mikhail Kondratiev (MI&DI). The description of first version released in the issue of ZX Format magazine in 1996 December, and the second variant published in the same year's in October in Spectrofon magazine. The Russian Spectrum newsgroup, fido.real.speccy released to public the parameters of scrolling mouse in his e-conference in November 2001. Meantime was appeared the three and four buttons versions. Great advantage of Russian versions using very few CPU resources.

The Czech and Slovakian Kempston Mouse was the development of Kompakt Services from 1994, and Proxima also sold an UR-4 version. In 1999 Hinek Gajda (HG Elektro) released the second version, it can connected directly to the Kempston joystick port. From these seems its basic disadvantage: it is not a real mouse, but rather a joystick compatible solution with the possibility of slowing down the cursor. Anyway, from it also derived its main advantage: works fine with most programmes, as Kempston Joystick is widely supported.

Velesoft also made his own versions primarily the basis of the Russian ones. First version appeared as DIY-kits, and supported only one button. The newer, green colour printed circuit board, named to Kempston Mouse Turbo 2006 has USB and PS/2 ports, and uses the second and third buttons also. Hard to believe, but we can attach two mouses to the Spectrum (with master/slave selection). Also has a video composite output. If it is even not enough, beside the external interface, they developed an internal variant too. They can speed up to 4x the controlling, which can be useful with older, classic arcades.

Kempston Mouse Turbo 2008 is made with new, improved and bugfixed board with Kempston and Fuller joystick support.

Kempston Mouse Turbo 2011 also supports Sinclair joy, as well emulates the keyboard. Now can be connected together two interfaces, again in slave and master mode. The manufacturing and configuring of the interface also became simpler. This version is made by the Dutch Ben Versteeg, who produced and sold earlier K-Mouses. The v2006 and the v2008 upgradable v2006 is made and sold solely by him with user manual and a scroller mouse. The v2011 can be ordered through the webshop of RWAP Software (SellMyRetro).

Most of Russian end user software and some games are supporting Kempston Mouse as standard, and Velesoft converted numerous old programs also.

Jarek Adamski also developed Kempston Mouse compatible interfaces with Yamod.ZXINPUT and Yamod.KMOUSE names. We can read about them right now.

ZXKit1 VGA&PAL board

Development of zst, the ZXKit1 VGA&PAL board is a device for Spectrum and its clones with the purpose to lead out the picture to VGA monitor or TV-set (through S-Video, and RGB composite).

By default, it is compatible with Leningrad, Scorpion, Speccy 2007, Pentagon 48/128, ZXM-Phoenix, ZX-Next and Robik clones. With firmware update, also works with Profi, Orion and Specialist machines.

It has two modes, selection is done by jumpers. First mode is centering the 256x192 Speccy screen on the standart 640x480 VGA (rest of the picture is Border). Second one is ‘upscaling’ the ZX picture to the VGA screen.

Can be ordered as empty PCB, PCB+parts, finished board with standalone VGA or VGA, S-Video and composite output.

Added: 2010. February 26.

Scart RGB to YUV Component Video Converter

Vitagecpu, who is living in the USA, describes a very interesting viewpoint for the Europeans. As on their TV-sets no Scart input (in full name: Euro-Scart), so standard RGB-Scart cables are useless. It needed a separate Scart-composite adapter also. In case of Amstrad CPC464 it gives black and white picture, while with ZX Spectrum 128K+2 it does not work at all.

The RGB-composite cable works, but the picture quality is far from the perfect (but still more superior than the picture of the RF modulator.)

So vintagecpu bought a Scart RGB-YUV Component Video converter. The 'case studies' on Internet describing half-successful stories. It sometimes works, sometimes not. Maybe you will get colours, maybe not. One of the two tried televisions (NTSC/Pal/Secam multi system) it worked perfectly with razor sharp picture. So we can definitely pick it up among the 'suggested' ZX Spectrum peripherals.

Added: 2011. April 02.

Jarek Adamski 's extensions

The already more times mentioned Polish Jarek Adamski, also offers numerous (or more exactly countless) novelties for the ZX Spectrum. Most of them realized meantime of the Spectrum SE development.

So, let's begin with Yabus.ZX. This one is an interface converter, to which connected into the edge connector of ZX Spectrum, gives the possibility to attach the Yabus devices designed by Jarek into the dual slot.

The prototype of this device was the Yabus.ZXMEM. This would offer three thoroughgoing edge connects and the same quantity of Yabus ports. All above, 32K EPROM and 32K SRAM would built into it. So, we could choose from boot-menu between the different devices (for example MB-02+, +D etc.). The Yabus.ZX due its design, it is much more safe like the Sinclair edge connector, and we do not have to care about the joining sequence. The compatible peripherals gave the Yamod. family name, so we will get know about them.

The Yamod.AYLPT is an AY-3-8910 interface made in two different versions: the basic Med only contains a serial and parallel port above the AY-chip, the more advanced Max got real time clock and has own EPROM also.

The card can work in ZX128 and Timex 2068 compatible modes, even in the mixture of the two. We can attach two cards to the computer in the same time, so one can work in Sinclair, another in Timex mode saving the valuable time of jumpering. In the same way, we can select ABC or ACB stereo with jumper. Thanks to the integrated slot, various peripherals can be attached to it: TC2068 joystick, Keypad or AY-mouse.

The card is useable in a reversed way through the parallel port: we can control the AY-chip with a PC. Some emulators are supporting this method, giving more vivid AY-emulation. In the Spectrum slang, these cards are called LPT-AY interface.

Yamod.ZXINPUT is giving possibility to attach PC keyboard and mouse. Mouse signals converted to Kempston Mouse. Keyboard layout stored in EPROM, so easy to modificate it. Macros also can recorded, and RS-232C port can used for serial communication too. Beside ZX, can used with SAM, Byte, and Elwro.

Yamod.ATBUS is an universal 8 bit IDE interface. Its purpose of using hard disks, CD-ROMs, Zip drives and CF cards with the Spectrum.

Transfer speed is above 200KB/sec. With some tunings can simulate the MB-02+, Interface 1-bis, ZXATASP and Divide interfaces as well Pera Putnik's creatures.

Beside the IDE controller, the board may contain a real time clock also. ZX, Timex, Sam and CPC compatible.

Yabus.IDE8255 realised by the 8255 chip and its aim to control IDE devices. Above the mentioned chip, only one logical circuit needed for building one. The internal 8255 chip of MB-02+ also useable with a special cable. Due to simplicity it is relative slow. The author engineered a CPC version too.

The ZX512 named memory upgrade was made in one and only prototype and designed for the 48K Spectrums and TC2048. This one can expand the memory to 256K or 512K, as well providing ZX128 and Pentagon 512 compatibility. Jarek was also engineered a Multicolor circuit for this device. Going forward in this artcile, will see, that Velesoft already finalized a similar card.

ZX4MB is the succesor of the previous. Only on Issue 6A board was tested. Thanks to the 4 megabytes expansion, this one is also compatible with ZX128 and Pentagon 512. Due to the size of memory, quite complex operating systems would fit into. Also Multicolor compatible. Optionally can used with the FlashD0 extender, which is a 128K PEROM card.

PL3MEM is a memory expander and an IDE interface on the same board. Memory consist of 32K RAM and 64 or 128K EPROM, which basically occupied by the operating system. The IDE interface is the already known Yamod.IDE8255 type. As the name points, it can simulate the work of +3(e) on 48K/128K/128K+2 and TC2048/2068 machines. It is possible to insert a 512K EPROM card into the place of original EPROM, so numerous alternative ROMs can be chosen. The Yamod.IDE8255 can also replaced with Pera Putnik's simple interface.

ZX bus splitter divides the edge connector into three. Some different subversions were engineered. The v004 offers some another sweets: DIP switches for selecting the active ports, reset and NMI buttons, serial port for Kempston joystick, and LEDs giving operational feedback.

With the Yabus.ZXISA card ISA cards can connected to the Speccy. So cheap serial and parallel ports as well floppy controllers can be obtained in this way. Through the HDD controller also we can connect joystick.

Another expanders which worth to mention: Yamod.EPROG is and EPROM burner, but practically useable as parallel interface. A Yamod.KMOUSE and Yamod.KMJOY are Kempston Mouse and Joystick interfaces. A Yamod.EPLIP is a fast parallel interface. A Yamod.PCMOUSE is a simple serial mouse card. A Yamod.SIO was made for radio amateurs: turns TNC modem the Spectrum. Finally, Yamod.ETHERNET a bit expensive Ethernet card.

All cards are can be ordered as DIY kits or ready made.

Miguel Angel Rodriguez Jodar's extensions

The Spanish Miguel Angel Rodriguez Jodar also belongs to the growing mass of active developers

In 2006 developed a 48K+ internal keyboard adapter. This is compatible with PS/2 keyboards and also with USB ones with adapter.

His original goal was to reconstruct the 48K+'s damaged keyboard membrane. It seemed to be very difficult, so finally he decided to build the adapter. With this we can record and playback macros, cursor keys are useable as Sinclair joystick and with Ctrl+Alt+Del combination can reset the Spectrum. The PBC can mounted into the empty place near the loudspeaker. The adapter was made a bunch of quantity for some friends. At present, Ben Versteeg is push it into small quantity production. This one is an external, horizontal interface, so fits well to any Spectrums.

For replacing the damaged memory modules was authored the SIMM adapter. Primarily was designed for fitting instead of the usually defected low 16K, but also useable for the upper 32K memory area, and to restoring both 64K banks of the 128K machine. The idea based on a similar MSX project.

The forthcoming project is still under development. This one is an ultra fast loader, with the purpose of speed up the loading speed from SD cards, CDs etc. Was successfully tested with Flash memory and achieved 180Kb/sec. The idea is based on Codemaster's game compilation CD, which was loaded games within 20-40 seconds.

The next development is already in prototype stage. This is a TMS9929-based MSX compatible video controller board. Its exact name is: MSX Video for ZX Spectrum.

The TMS chip itself is a video controller for general purposes, which is also used in ColecoVision and TI/99 beside the MSXs.

Which advantages can obtained with such a card? We can highly superior the characteristics of the original ULA, as it can control his own 16K video Ram, and the video controller does not uses the resources of the processor. It communicates thought two ports with the CPU, so acts like an external peripheral.

The new graphics modes are the followings: Text: 40x24, monochrome; Screen1: 32x24 chars, 256x192 pixels with sprite support; Screen2: 32x24 chars, 256x192 pixels with 8x1 attributes again with sprite support - this mode is best for quality games; Multicolor: 64x48 big pixels, although each pixels can be different colours.

The card contains the video chip, some DRAMs, a GAL 20V8 circuit. The purpose of GAL to reduce the necessary amount of other circuits, as well is easy to reprogram.

There are some examples about rewriting some MSX programmes of which source codes was given by the Spanish MSX community to the developer.

The card is compatible with all Spectrums.

Dr. Beep's extensions

Ymond Reconstruction Service (YRS) is a Dutch team was founded in the classical times of ZX Spectrum. At the moment, has only one active member, Dr. Beep, alias Johan Koelman.

Dr. Beep's ZXPC interface is connecting the ZX Spectrum with PC through a parallel port. The interface realised with combining two cards: a simple I/O card and an EPROM circuit. With this, . Z80, .SNA. .SCR and .TAP files stored on the PC can be loaded into the Spectrum. In the near future, supporting of .MDR (Microdrive) files is also planned. 48K programmes are loading within 7 seconds.

Dr. Beep is also developing a hardware ZX81 emulator for the ZX Spectrum. This one is realised by a selectable 32K ROM combining both machines' ROM routines.

Sami Vehmaa's extensions

The Swedish Spectrumist, Sami Vehmaa's developments are quite interesting, as he making continuously the various interfaces, which can expand the possibilities of ZX Spectrum in very different ways.

With the ZXCF, ZXCF+ interfaces, we can use Compact Flash cards as storage devices for the ZX Spectrum. The ancestor was already born in 2003, plus version is the fruit of 2007 year and the +2 upgrade, which is connectable to ZXCF+ was made in 2008.

They driven by the ROMs containing ResiDOS, which we got know about the ZX Spectrum +3e. The card is supports both load and save commands.

His most crispy development is ZXMatrix, which combines ZXCF+2 and ZXUSB cards. Between the two modes we can select with jumper or switch. Main features: 1 megabytes of RAM, USB 2.0 support and high speed CF reading-writing. Vehmaa also made his own version in only one piece. It has 2 megs of RAM and built-in Kempston joystick port.

ZXATASP interface is an earlier development of the author. This is a 16-bit IDE interface with hard disk and Compact Flash card support. The memory can be 128 or 512K. ResiDOS also supporting this device. ResiDOS could be loaded into this memory, so not necessary to rebuild the Spectrum. As the winchester needs an external power supply and the same time of falling down of the prices of CF cards, this card becomes less important.

He was also engineered his own ZXAY interface. It contains the AY-3-8912 chip and suits for 16/48K Spectrums. In the classic era lots of manufacturers and amateurs made similar sound enhancements. This one is sounds in ABC stereo.

The ZXMEM interface is expanding from 512K to the nearly unbelievable 32Mbytes the memory of 16/48K Spectrums.

Vehmma also made a real time clock (with date and time) and a high-speed serial port too.

ZXEXP adapter is an expanding tool, which thorough ZXBUS (the own inventment of the author) could offer the possibility of attaching more interfaces at the same time. All of the author's cards are equipped with ZXBUS. And the last four units only have this expansion system. This ZXBUS of course not the same, as the Russian Nemo-developed standard.

His laptop will be described in a separate section.

Velesoft's extensions

Russians cracked the European ZX Spectrum machines and peripherals, and with adding their own innovations, re-engireed and manufactured them from Russian parts. The Czech Velesoft recracked these circuits, and built the Russian novelties from European ingredients. In his homepage, beside the 90's development we can faced with the freshest peripherals. Not only for the ZX Spectrum, but also engineering for Sam and Timex Sinclair.

Kempston Mouse (Turbo), Turbo Sound Easy, his divIDE upgrade and the PS/2 ported Proface AT were already introduced.

Sound Mixer for Turbo Sound Easy is a mixer, which control the Turbo Sound ABC/ACB, SAA stereo and beeper channels, so a 12+1 channel mixer.

The Pentagon 512 interface is an internal card for ZX Spectrum 128K+2 (only compatible with Issue 3). The timings of Pentagons are different from the ZX128, in addition, all memory banks and ports are handled as fast ones (Fast IO mode). So programs made specially for Pentagons, are more or less incompatible with the original Spectrums. The interface also solve this problem beside the memory expansion, which is realized with one piece 512K SRAM module. Thanks due to the Pentagon mode, original ZX Spectrum programs are also running faster, which is handful for compressors, image editors etc,

It also contains a 128-512K FlashROM, in which we can store alternative operating systems. This upgrade also supports the Unrain function, and co-operates with the D40/D80 systems. Some of the utility, such as MDOS File Commander and 128Tools using the full memory, so do not have to care too much with changing the discs.

The External 128-512K upgrade for ZX16/48K is similar to the previous, but this one is an external interface made for the 16/48K little brother. In the case of 48K machine, the higher 32K must be removed. The card works with 128 and 512K SRAM modules. When 512K one used, the machine will be compatible with Pentagon 512K and also will be faster than a ZX128. Of course, it is possible to switch off all extras and go back to the ordinary 48K mode. Unfortunately, the expander do not supports the shadow videoRAM, but using of the extra ROMs are possible.

The successor of Pentagon 512 interface is the ZX Profi interface, which gave its name from the similarly named Russian clone. It works only with the Issue 3 grey 128K+2 Spectrum, and its roots going back to 2004. Velesoft refreshed the old project, and fully redesigned the interface.

1 megabytes of RAM, 512K FlashEPROM, a Z80 processor and a battery take place on the single circuit board. ZX Profi 1024, Pentagon 128-1024 and Scorpion ZS 256-1024 compatible. DivIDE, MB-02+, ATM Turbo and Russian cache emulation is under construction.

A ZX 128K ULA clone is also under development. Seems, will be soon built the next Czech superclone...

Data Gear was initially engineered as the part of MB-02+ interface. Just to remember: originally its task was to speed up the access of HD disks, but the additional power is used as hardware accelerator nowadays. Its main advantage to produce Multicolor effects without vibrations. In 2005 and 2007 was pushed into production one-one series.

Hyperface is a new type interface. Contains three ports with direct access, as well one conventional one. Velesoft into his own interface packed a divIDE and Kempston Mouse Turbo interfaces.

In 2007, also designed his own ProfROM clone. It only exists on ’paper’, and did not tested even by the author.

Updated: 2010. January 30.

Pera Putnik is one of the oldest Spectumist, who started his DIY website with various developments in the new age. Primarily mass storage devices are in the centre.

Among the smaller developments, there are various ROM modifications (as external ROM, Flash EPROM and switchable ROM), NMI button, RGB connector, floppy interface (which unfortunately uses its own file format).

He becomes well-known from his IDE interfaces. The simply Pera Putnik IDE interface called device has two variants. First one is 16 bit, the second one is using 8 bit technology. The one and only disadvantage of the 8 bit system, that capacity of hard disk will be half of the nominal. But in the case of ZX Spectrum, this fact is easily ignorable. The teenager developments works fine with modern Flash and Compact Flash cards - last one needs a CF-IDE adapter of course. Transfer speed is around 150K/sec, which is more than enough for Spectrums. ZX Spectrum +3e is also supporting these devices.

Listening to the voices of technology, also engineered his own Compact Flash interface. This is also 8 bit system, and using the full capacity of the cards. Based on the 8 bit IDE interface.

Cygnus's enhancements

The Czech Cygnus, alias Pavel Cejka also offering some self developed hardware, which documentation is available on his website.

About his own versioned Miki RS232 interface we could already read.

The ZX IDE Interface is very similar to Pera Putnik's, although the author is suggesting the use of DivIDE interface. Anyway, it works without problems with ZX Spectrum 48/128K+2 and Didaktik Gama 89 machines as well with Beta interface. But it is doesn't like too much the Multiface 128 and Diskface plus interfaces. The available software is in Czech language, and supporting all basic functions.

Also giving some ideas to connecting ZX Spectrum and LCD monitors. On the homepage, there is a detailed description, how to succeed to connect a Spectrum with a Playstation 1 LCD screen. Anyone, who would like to connect any type of LCD monitor to the Spectrum, worth to read to avoid some traps.

A really innovative novelty is the connecting of PCL printers. Spectrumists were dreaming about the possibility of colour printing. But with the exceptions of some colour matrix printers there were no choices. Matrix printers are noisy, printing speed is low, and also the quality is far from the perfect.

As Cygnus is working as a service technician, got positive experience with the PCL language printers, so targeted these ones. He was designed a special Didaktik inverter PCB, to which is connected to a Canon standard parallel port (not Cnetronics, because Canon is more easy to finalize).

Due to the PCL language, all HP printers with LPT port made between 1995 and 2088 will work, but primarily works brilliantly with DeskJet 340. In theory, works fine with the printers of another brands too.

The drivers are supporting the 75-300 dpi resolutions, normal and draft modes, as well setting up the margins.

At last, but not least, we will get some ideas to work with the Aritma 0507 plotter. This is an old Czechoslovakian plotter, which was released in some variants, but they are differing from each others from minor details.

The plotter is connecting through the UR4 interface to the Spectrum. It has two superior technical details, which are better, than its contemporary machines. First, it using 1x8 bits to control all motors, while others are using 3x4 bits for each ones. Another, that it is using the more reliable screw mounting for the pen.

Cygnus was tried the most different printing techniques and sharing them with the publicity. He is printing with the original MZR driver from BASIC, making vector drawings with the Desktop software, and also using the serial port of SIF.

Droy's extensions

Droy living in Spain since 2002 surprised with numerous inventments the Spectrum community.

Supposedly, he must be an Interface II fanatic, as lots of his work in connecting to it.

His own Interface II clone (without the joystick ports) consist of two wired ISA connectors. Also made game cartridges with enhancing the original conception. On original cards only 16K games can stored and played. He was improved it to one 32K game or selectable two 16K games.

ZX-Flash Card is a further more developed device. With a 512K capacity card we can choose from 10 pieces of .SNA files, sparing the more minutes 48K loading times.

Engineered a new PlusD interface too, but that was mentioned earlier.

The IMAR-3 PC-AT keyboard controller is his creature too, which gives the possibility of connecting AT or PS/2 standard keyboards. Sadly, only 48K and 48K+ compatible. But thanks to the thoroughgoing edge connector, another peripherals easily can attached to it.

Some methods of replacing the dead keyboard membranes also come from him.

The English Paul Farrow is best known as a ZX Interface 2 expert in the Spectrum community.

These cartridges are not very well known, so begin this section with some introduction about them.

The 16K ROM cartridges fits into the special slot of Interface 2, was released on the market in September/October of 1983. In a sense, they turn the Speccy into a 'gaming console' - with zero loading time and zero loading error. Despite these positive things, not widespread very much, because 48K games became mass dominant. On the other hand, the loading time of 16K games was much more shorter - so did not worth to switch as an option of the tape. Sinclair Research also released a Test cartridge for diagnostizing the faulty Spectrums, these were used solely by the service centres. The Parker brothers produced some prototype cartridges too, but they were not public released.

Originally, cartridges contained a single 16K ROM (Standart 16K ROM Cartridges - method 1.).

The simple design of cartridges makes it easy to reproduce similar devices. The shortcomings of Interface 2 can be compensated by modifying the 'inner circuits" of the original cartridges. So the 'magical' 16K limit is easily breakable.

One of those facilities, when burning more 16K ROMs into a larger capacity EPROM and then select from them the desired ROM content (Shwitched Bank Paging ROM Cartridges - method 2.).

The next method is to read and map more single 16K ROMs into the RAM, then put them together into a single file. This was first used by the Spanish Droy, who burnt the Knight Lore game into a 32K EPROM (Timed Bank Paging ROM Cartridge - method 3.).

A more advanced method the software controlled reading-mapping technique (instead of the previous method, when timing was controlled by the electronic circuit (Software Bank Paging ROM Cartridges - method 4.).

At last, it is possible to enhance the previous functions with the possibility of re-programming the Flash EPROM directly from the Spectrum. Then the maximum ROM size is 128K due to the limitations of Spectrum's memory (Programable Software Bank Paging ROM Cartridges - method 5.).

Paul made three separate generations from the cards: ZXC1, ZXC2 and ZXC3. These are available as empty PCBs, ready-populated PCBs, cased PCBs and ready-programmed cartridges.

The characteristics of different generation are the following:

ZXC1 is handles the 1., 2. and 3. methods. Supports 8K, 16K, 32K and 64K EPROMs. Two subvariants were produced: first batch has silvered edge connector, the second got goldened to improve elelectric contact (otherwise, the two PCBs are identical).

ZXC2 supports 1., 2. and 4. methods. Possible EPROM sizes: 8, 16K, 32K, 64K 128K and 256 K. In addition, it supports re-programbale 128K Flash EPROMs - but it is only possible to program them with an EPROM programmer.

The most current version is ZXC3, which extends the capabilities of ZXC2 with the possibility of re-programing the Flash EPROM directly from the Spectrum. The card utilises the 5. method, as well the standard and simplified 4. method. 8K, 16K, 32K 64K and 128K EPROMs are supported, and it is backward compatible with ZXC2 up to 128k. With a simple modification, ZXC3 also can be enhanced to 256K.

For all of the three cards usable the Windows-based ZX Cartridge Utility. With this, .Z80 and .SNA files can burn into the EPROM with an EPROM programmer.

As mentioned above, in the case of ZXC3 does not need an EPROM programmer. Via the RS-232 port binary data can be sent to Spectrum. From that point, the Speccy can program the content into the Flash EPROM. For ZXC3 also available a Microdrive emulator ROM, which offers 75K storage by the BASIC commands of Interface 1.

The SPECTRA interface is a multi-purpose interface for the 16K/48K ZX Spectrum. Its primary function is to allow the Spectrum to be connected to a TV via a SCART socket to produce an RGB picture that is sharp, bright and completely free from dot-crawl.

SPECTRA interface plugs into the expansion port of the Spectrum and connects to the TV using a standard SCART cable. There is no need to make non-standard modifications to the Spectrum since the interface only requires access to those signals available on the expansion bus. The Spectrum's sound is also directed through the SCART connection to allow it to be heard loud and clear through the TV speaker(s). The clarity of picture and sound is equivalent to that only seen when using the monitor socket of a 128K Spectrum or a Spectrum emulator.

An exciting additional feature of is its ability to extend the Spectrum's display to support 64 simultaneous colours and at a variety of increased vertical resolutions, resulting in a total of 12 different display modes! Support is also provided for multiple screen banks, similar in concept to that featured on 128K models. At long last, the limited colour abilities of the Spectrum can be overcome, opening the potential for new visually stunning programs.

It also provides the following: a Kempston joystick socket, a ZX Interface 1 compatible RS232 socket, ideal for connecting to a printer, modem or a PC, a reset button, optional support for a ZX Interface 2 ROM cartridge socket, optional support for an onboard ROM to override the internal ROM. Further features: the ability to extend Spectrum BASIC via a ZX Interface 1 compatible paging mechanism (offering the potential to extend BASIC with commands to drive the new display modes); a rear, full width gold plated expansion bus, a set of configuration switches to allow each new facility to be enabled / disabled, ensuring full compatibility with all existing hardware.

All features come as standard, apart from the ROM cartridge and onboard ROM facilities. These are mutually exclusive and so it is left open for the user to fit whichever socket (if any) they prefer. Should you wish to use a Zero Insertion Force socket with the onboard ROM facility (useful if you intend to develop your own ROM software) then it is best to fit a turned pin socket first and plug into this. A standard IC socket is more suitable when you don't need to change the ROM very often.

This interface is constructed from a professional made board that measures only 10cm by 10cm. The interface will only operate with 50Hz models of the 16K / 48K Spectrum, but is not supported by any model of 128K Spectrum (a specific version may follow if there is sufficient demand).

It may prove necessary in issue 1 and issue 2 Spectrums to fit a wire link inside the computer to ensure a required video signal is exposed on the expansion bus (this optional wire link was fitted as standard in later builds of the Spectrum).

Another area of DIY section the Scart leads for the various machines. Of course, we can buy them ready-made (see later), but there are full documentation for tinkering to all machnies including 128K (both UK and Spanish version), 128K+2, 128K+2A/B and 128K+3.

At last, there is information about how to rebuild the 'mysterious' Keypad (the attachable numeric keyboard) from contemporary parts. This one is originally designed for the Spanish 128K, but excellently works with the UK version as well with the 128K+2. He was realized it on a simple veroboard, but the printed circuit diagram is also downloadable from the website.

Gondos Csaba's extensions

Gondos Csaba (GoCom, Gondos Computer Communication) is the main constructor of Sinclair.hu and also a radio amateur. His first interesting development is the Smartmedia interface working with 8, 16 and 32 megabyte cards. It needs to modify the ZX Spectrum ROM routines. On the homepage also can find some utilies and source codes for the interface software.

Another two novelties, the G-Tech analogue joystick interface and ROM-extension are connected to the game Ghost Castles from WSS Team. G-Tech interface connected through the Kempston interface, and supports analogue joysticks. ROM-extension is a 256K extender attached to the Interface 2. Only this game is supporting yet. All documentations are freely available.

The next two peripherals are quite similar to each others. Their joint feature that they are working as a 'digital tape', but they look like a different peripheral. TZX mouse is a TZX player with 8 megabytes of internal memory, working from button battery and capable to handle maximum 256 files. With a battery, averagely lasts for 100 hours, and also supports turbo loading up to 4x speed.

Joytape player is also a common development with WSS Team. This player was presented on the Megabit X 2010 club meeting. But it was ready as a prototype built into a garage bell box in 2009. Integrating the thing into a joystick was the idea of Gyorgy Papp (Pgyuri) as the creation of the name of the device also. The device priced at 20 Euros, and certainly contains all WSS games pre-installed.

Another developments: reducing the power consumption in more steps and reconstructing the keyboard membrane from micro switches.

Scott-Falk Hühn's extensions

Scott-Falk Hühn German tuningmaster offers some smaller-bigger tips for turbocharging the 48 and 128K Spectrums.

Similarly to Paul Farrow and Droy, he also made Interface 2 cartridge clones. In the same way used 512K Flash-EPROM, giving opportunity of using 32 different 16K ROMs, but currently only 16 of that are used. Choosing is done by a manual selector. Not only games, but also various ZX80, ZX81 or test ROMs can be loaded.

For the rubber keyed mate offers composite video output and reset button.

Improving of 128K video output is done by desoldering a capacitor and a resistor (quite surprisingly, they are even missing in the 128K+2). Of course, the picture of 128K+2 is also far from the perfect, he was doctored the problem with part replacement. This improved picture quality was further improved with separating the audio signal from the video output.

Certainly, the 128K sound was not too very perfect for him: the beeper was too loud, and AY music was too quiet, so made a small circuit to solve the problem. And the 128K+2 also could not avoid this modification, here the noisy tape loading voices also were quieted.

According to his needs, mounted a third RS-232C/Midi/Keypad port into the machines.

With a selectable 64K EPROM, beside the 128K+2's own ROM, the original 128K ROM is also available for compatibility reasons.

Finally, re-wiring of the nonstandart 128K+2 joystick ports are also done.

On the picture all 128K+2 modifications seen.

Ben Versteeg's extensions

From the hardware stuffs of the Dutch Ben Versteeg we already spoken. Only to call up the informations again, let's talk about once again the things, which are realized by the international co-operations.

He planned to improve the originally Czech developed MB-02+ disc interface with the name of MB-04, but Ingo Truppel (with who he is in friendly relation) overdriven him.

The similarly Czech Velesoft's Kempston Mouse Turbo interface is producing in small quantity with attaching English instructions and an optical scroller mouse in the deliver pack.

The external version of Spanish Rodriguez Jodar's internal PS/2 interface is also taken into production.

Recently, he thinks about integrating the previous two boards, so maybe we except a mouse+keyboard combi interface.

Through his blog can informed the latest news, and the actually ready assortment is advertised through EBAY, and he delivers by post the ordered goods.

Even further, created a stereo converter for the 128K Spectrum. This is a mini PCB, which is placed on the top of the AY-chip. The card supports the ACB and ABC stereo standards, we can choose by shorting or by a switch between them. The beeper is coming from each channel, volume is fixed.

Despite, that it gives crystal clear sound, got fairly much negative comments on the WOS forum. So Benji stopped its development. Anyway, the series of the first line is ready, and the documentation is available from the homepage.

The also similarly Spanish Jose Leandro Novellon is again offering some good ideas to enhance the ZX Spectrum with various interfaces.

Let's study first his RAMJET interface clone. The original one was the development of Microsat Hardmicro released in 1990 in Spain. Was planned for the ZX Spectrum +2A/B and +3, unfortunately will not work with the earlier models. This is a Multiface-like device, we stop running programs, insert pokes, and can save the programs to either to tape or disk. So, the Spanish solved the problems of the copy-protected disks. Jose not only cloned the card itself, but its box is also very similar to the original.

The external interface ROM is supporting the use of custom ROMs, without tinkering inside the Spectrum - can be gentling for those, who always planned a similar extension, but do not wanted to hurt the Spectrum. With a selector switch we can choose between the original ROM and the EPROM, and got an NMI and reset button additionally.

He is an enthusiastic user of Garry Lanchaster's ZX Spectrum +2E/+3E clone, but like another users, was irritated by the use of power supply and the noisy operation. That's why he changeover to the Compact Flash cards. He describes three submethods of using them. Fist one is using a simple CF-IDE adapter for the already available board. Its main disadvantage, that the CF card still must be feed from external power source.

So made some own constructions, which named jointly to Compact Flash +2E/+3E interface. First version included the IDE controller and the solution of power supply on the same PCB, but without the CF slot. Immediately constructed an inetrnal and external version. Further development of this card is a complete interface, which integrating also the CF-slot on the board.

The gamepad of Sony Playstation 2 also successfully connected to the Spectrum with the Gamepad PS2 adapter. This using the two joysticks ports. Author is suggesting the use of Sinclair 2 compatible interfaces, but theoretically compatible with all types. Works smoothly with Dance Carpet, but has some problems with the guitar of Guitar Hero.

Also cloned Interface 2 cartridges, the TTL version was soon followed by the more compact GAL chip variant.

All above, some smaller or bigger own modifications (faulty sound jack and PAL chip replacement, ROM exchange) and analysis of classical devices also can be found on his website.

The again Spanish Aitor's internal IDE interface is based on the card of Jose Leandro. After a simple bugfix, and learning the low cost finalisation of the board started to construct it.

The interface is mounted into a 128K+2A machine, into the place of the cassette unit. To be sure, built in a jack connector, if sometimes want to load from tapes.

The card must plugged into the socket of Z80 processor. At the moment, this one is also only uses the half of the nominal capacity of IDE devices, as it is an 8 bit card. Aitor wants to further develop it with a switch, with which easy to choose between the low 8 bit and high 8 bit areas of the card, and accessing the whole 16 bit capacity in this way.

PCWKing's extensions

The English John R. P. King (or as he calls himself: PCWKing) principally well-known about the tune-up of Amstrad produced computers. So, among the whole range of CPC, PCW series and the NC100 machine, also using the ZX Spectrum +2, +3, +2A and +2B.

The DIY section can be divided into two sub-parts in case of the Spectrum: making of various cables and modification the Achilles-point of +3, the floppy system.

The first cable is a monitor cable for attaching CPC monitor for the +2, +3, +2A and +2B. Well, this is basically a converter cable between 8 Din (Speccy) and 6 Din (CPC) connectors, which gives superb picture with the CPC unit. Unfortunately, sound is not driven by this method.

Similar is the RGB-Scart converter cable for +2, +2A and +2B machines, this was designed by Alan Cox. It also contains some resistors. Opposite of the previous cable, this also contains the sound output (in mono). The picture is far superior, which can be obtained on a monitor.

The next DIY cable is Centronics cable with which standard printers can be connected to the Amstrad-originated Spectrum models.

The last cable (which is also the most simple one) is a tape cable for the +3. Here a stereo jack is converted to two mono ones (MIC and EAR).

The another area may catch the interest of +3 owners is the different floppy disc modifications.

The most simple one is the external 3 inch drive attachment method. For this only need a standard PC 5,25 inch cable floppy cable, from which maybe cutted down the unnecessary second floppy connector.

Adding a 3,5 inch unit is muck more trickier. As 'modern' 1.44M and 720K drives working solely with 5V, the 12V line line from Spectrum must be cutted down or must be fitted a 5V regulator.

Another difficulty, that not all 1.44M drives are working fine in 720K mode, as they missing the 'Ready Signal' (this is indicating, if there a floppy disk in the drive or not). For testing this feature, there is also a hint on the homepage.

The next problem is if we have the compatible floppy drive, that they will use 180K as standard. For solving this problem, there is also a simple side switch circuit on the homepage. This issue is also can be solved with a ROM replacement.

Módosítva: 2010. augusztus 07.

Graham's extensions

Graham also primarily focused on the Amstrad manufactured machines, and also made modifications for attaching an external floppy drive. Opposite of PCWKing, he not only trying out the possible compatible 3,5' drives. He went further, and constructed his own disk-ready -> disk-change signal converter board. With this, easily can be compatible with all floppy drives the ZX Spectrum 128K+3.

Construction is quite simple, based on a 74LS38 type logical gate. By the way, for the another retro (made before 1990) computers the circuit works fine. If not so, with utilizing the rest gates of 74LS38 there is also possible solution on the webpage.

In addition, Graham also introducing a regulator circuit, which solve the 5V power supply needs of the floppy drive.

He also worked on the further development of 128K+3e. For starting point, used the Pera Putnik simple 8 bit interface. For the first attempt, the power needs for the HDD of an old laptop is feed from the power connector of the Speccy's PCB. The shortcoming of this method, that during power on, the hard disk do not get enough power to spin up fully, so the +3e will not recognize it. It can be solved by pushing a simple reset.

In the second version, the winchester was replaced with an 512K micro memory module, which is an early version of SDD. This has low power consumption, and has no spin-up time, so adopting the previous method, no need to reset after power up. The circuit remains the same, only the socket of card became vertical.

After upgrading the ZX Spectrum 128K+2 to +3e, in this machine was moved the old laptop hard disk. The power now comes from the CPU.

Also we can read about a 128K+3e modification for the ZX Spectrum 128K+2. The size of the original ROM of +2 is 32K, and +3 uses 64K ones. As these old ROM modules can not be bought as new, Graham used a 128K EEpROM. For building this modification, also necessary a 28-32 pin converter. We can choose with a switch from the extra ROM the necessary ROMS: 48K, 128K+2 or 128K+3e.

Updated: 2010. September 26.

The first novelty is an universal 128K expansion for ZX16/48 (all issues) and Didaktik Gama machines (all subversions).

Its designer was Zilog and it is the third revision of the hardware. Fully compatible with the original 128K and FastIO and Unrain is also supported.

The tuning is consists of two main steps: installing and wiring the new chips and then building their controlling logic. This modification for advanced users.

The Simple AY-interface is based on MDV's idea. The ABC stereo mixer constructed by Zilog's 'golden ratio'method, so the best AY-sound is guaranteed.

Simply have to to place the components onto the universal board and wire them. Can be mounted internally or can be build as an external interface. In the same year, Pavel Urbancik designed a neat PCB for it, which was named to Nice board.

The Memory LED map is the creation of z00m and Busy. This contains 64 LEDs inline or as a 8x8 matrix. Each LED represents 1kB of memory, which flash up when the CPU reads from it (very useful when cracking).

Components can be placed onto the universal board or onto the authors' prototype PCB. Can be mounted internally or built into an existing interface (MB-02+, Betadisk, +D...)

The Dual color memory LED map is the further development of the previous device made by Ik0n. Can be ordered through E-Bay.

The Bank LED map of z00m is indicates the function of port 32765. It works with 128K and 128K+2 machines.

On the picture, the previous version is seen. The new one has a slightly modified circuit diagram, but functionally is the same.

Z00m did not placed the LEDs onto an universal board, but sticked them from internally onto the case of 128K+2

The simple D40/80 modification for 128K or 128K+2 is also Zilog's development (anyway many others also made similar modification).

After the simple rebuild, with a switch can select between the standard 128K or the D40/D80 compatible mode.

The ZX Spectrum +3e^2 machine of Ik0n is the further development of the ZX Spectrum +3e. Its main purpose to stay compatible with both the original +3 and the +3e. First task is to make the ZX Spectrum +3e conversion along with the two selectable ROMs. With a switch, the default mode is +3 (DivIDE) and the another is the +3e.

Among the +3e extensions, he was chosen the 8 bit Pera Putnik CF interface due its simplicity. As home-made soldering of the CF slot is quite difficult because of the small size, so he choose to solder of the IDE socket instead. The CF card can be attached through a separate CF-IDE converter. The slot of the CF card placed bellow the already replaced 3,5' floppy disk drive.

Also we can find both for the grey (128K+2) and for the black (128K+2A6B) Spectrums complete developments, which are named simply to 'ugly hacks' by the author. These modifications are really cheap ones, so no idea, why Amstrad did not applied them.

The 128K+2 tuning begins with the RF and composite video mod. First step is to solder out the C31 condenser, which mixes the picture with the sound. Of course, the sound will not will be heard through the TV speaker, but it will be resolved later. In the case of composite video mod, simply have to rotate the TR4 transistor, if the picture is distorted or black and white.

The already mentioned unrain bugfix is also can solved in the case of 128K big brother. The original PAL10H8 chip must be replaced with a reprogrammed GAL16V8 chip. The recompiling, which was necessary for the bugfix, was done by Poke Studio.

The ACB stereo output is also known already. The beeper is connected to both left and right channels of the ACB stereo mixer with a simple transistor amplifier through two 1K resistors.

Owners of 128K+2A/B also may get some ideas for the ugly tunings.

The RF out and video composite mod s similar to the above, but here the C24 condenser must be removed. The composite video output is completely missing from this machine. Suggestion: to fit inside the original circuit of the 128K+2.

The sound of black machines are even worse compared to the +2. The ACB stereo tuning is very similar to the previous, but here must be applied 2 pieces of 2K2 resistors as the beeper is a bit louder.

The Old ROM replacement is for those, who has not have the v4.1 ROM, but owning the older v4.0. Although the new is still not perfect, a lot of bugs were corrected. Needs two 27C256 EPROMS for this modification.

Updated: 2012. Nov 01.

The SinDiKat community was founded in 2009 in Bratislava, Slovakia. The meaning of abbreviation is Sinclair a Didaktik - Klub Aktivych Technikov, that is Sinclair and Didaktik - Active Technicians' Club.

The head of this the already introduced Ik0n and more respected persons (eg. Noby, Busy) and teams (ci5, Zero Team) joined to the initiative. Their hardware and software developments are presented in the meetings to each other - meanwhile they are communicate on-line.

The first hardware-hint is the construction of Philips HCS 130 Videotext Terminal's keyboard interface for the Speccy. The keyboard was bought in 1992 by the host of the blog, and was used until 1995, the end of his active Spectrum era. The frequently used floppy and printer commands are mapped to the function keys. A number of special buttons are working as the usual 'double combinations' of the Spectrum.

Ik0n also published a 128K expander, which Matsoft sent him in 1994. Memory paging is completely 128K compatible, but using the second vieoRAM is not solved. Although today is technically much more advanced methods are available for constructing such expansions, for the fans of classic tuning is worth taking a look at this well.

The next innovation is to enhance the ZX Spectrum +3e with DivIDE support, this is the ZX Spectrum +3e^2.

From the +3e enhancements, Ik0n choose the 8 bit Pera Putnik CF interface due its simplicity with a single change. Since it is difficult to solder the CF slot connector because of small size, so choosen to solder an IDE connector. The CF-card is connected via a separate CF-IDE converter.

The next step is to build in the suitable double-sized EPROM. The first position is the +3 mode (DivIDE) in the other, the +3e ROM can be used by default.

The CF card slot is placed under the already changed 3,5' floppy drive.

Also we can read about restoring a Didaktik Gama 80K.

The machine was bought from auckro.cz without any cables and power supply. The motherboard seemed good, except from the missing antenna connector.

For the first time, the bad memory chips were replaced with the controlling circuit. For sure, 128K memory is incorporated instead of original 80K - leaving open the possibility of future expanding.

First only the low 16K, later the upper 64K worked fine.

After cleaning the housing, the base paint, then the final paint was done. The keyboard was renewed with an alcoholic marker. This was followed by replacing the missing LEDs, along with the reset button. The antenna connector is replaced with a cinch socket. At last, the power supply was an USB/PATA converter box after replacing its original power connector.

Hozzáadva: 2010. május 22.

KempAY interface is the first own development of Lotharek, which was begin in November 2009. This is a combined card of a Kempston Joystick Interface and AY-card, and it is also Sinclair joystick compatible. The joystick part has only one connector. The AY-part is 128K compatible. Of course, it has a thoroughgoing edge connector. The further development of this card is KempAY CPLD, which was made with ATF1502 CPLD and contains a joy tester and a reset button. Got two RCAs instead of the stereo jack.

The interface is not available now, but sliced into two parts, can be ordered by anyone.

The Angry Space Invader (on white or black PCB) is a Kermpston and Sinclair interface. Again built with the ATF1502 CPLD and its extras again the LED joystick tester and reset button.

WonderAY is a standard AY-interface. The price does not include the sound chip, but of course it is also can be ordered.

His DivIDE 57c clones clones, DivIDE 2k11, USB HxC and SDCard HxC Floppy Emulator already mentioned some paragraphs earlier

Updated: 2013. April 27.

The Brazilian Victor Trucco primarily is modificating the Microdigital mamanufactured TK clones made in his own country. But he has also some ideas for improving the ZX Spectrum 128K+2 also. Let's see them first!

The Beta 128 Plus interface is the SD-card version of the previously mentioned Beta-128. This is based on Jorge Braga's 'wired' Beta 128 interface, after his friend, Marcus Garett sent him to repair.

After repairing the interface, Victor made the PCB variant of it based on Braga's document. This is more neat, smaller and also more reliable.

The following minor modifications are making easier the life of (Brazilian) ZX Spectrum 128K+2 owner.

The first mod is a simple one with the purpose of making available the Spectrum work with 110V power supply (which is the standard in Brazil). This type of supply can be bought nearly everywhere, but the Spectrum needs reversed polarity. The most simple way to rewire the supply itself, but it means the lost of guarantee. Instead of this, he is suggesting too crossing of LK5 and LK6 jumpers inside the Spectrum to achieve the desired result.

The next modification is a power-button building in placed bellow the cassette recorder. I think, it does not needs further explaining.

He also offers two variants for making the composite video output.
The root of the problem, that the original video output is made for the English TVs, and does not work with the Brazilian PAL-M standard (except some Philips and new LCD TVs).
In the first version, the 2N3904 transistor have to be replaced to BC237. After all, we have to make sure, that the LK1 and LK4 jumpers are closed, and LK2 and LK3 are open. We also have a problem yet: when the Spectrum plays sound, the picture is distorted. For resolving this, needs to resolder the C31 condenser, which mixes the video and audio signals.
The second version (which can be also applied for the +2A/B and +3) means a built of an alternative mini circuit. The best to place it into the original modulator, after we put out its original content. After it is done, we only have to resolder the C31, which is C24 in case of +2A/B and +3.

The next modification is the stereo output. First step is to separate the audio signals from the video signals. It needs to connect the R37 and R45 resistors. For setting up the required volume, it is suggested to replace the R37 to a 4,7 kOhm one.

The last, but the most interesting mod for most owners, is a how-to description to use the standard Atari joysticks.
The first version is more difficult, and necessary for only those, who's joystick chip controller is faulty. In this case, we have to connect the keyboard buttons to the joystick ports (1, 2, 3, 4, 5: joy1 and 6, 7, 8, 9, 0: joy2).
The second version is more simple, it is a basic re-wired converter for standard joysticks.

Hozzáadva: 2010. október 16.

Alistair' enhancements

Alistair, who is living in the Untied Kingdom, is offering some ideas for tune-up the ZX Spectrum 128K+3. The Flash ROM Adapter card is replaces the two original EPROMs with a single reprogrammable Flash chip.
Its first prototype was made with the W29EE01 'write once' ROM, while the second contains the 128K AM29F010B Flash ROM. All of two was built on tripad, the final version on PCB. The card can be ordered for 10 ponds + postal costs.
Keep in mind, it is only 128K+3 and 128K+2A/B compatible, other models not supported.
From the twice 64K ROMs we can select the desired one by a jumper or switch.
The Flash programming utility can be downloaded under Windows or Linux.

The next thing is to modify the sound of ZX Spectrum 128K+3 to 128K+2B. As we know, the +3/2A were released with buggy sound. This error was corrected later on +3B/+2B mainboards. This factory modification can be applied on the original mainboards. This means of replacing six resistors, and adding further two.

Added: 2010. november 20.

Winston's enhancements

The first peripheral of Winston, the Spectrum Flash ROM and Diagnostics Board was built for the 25th anniversary of the Speccy. Producing this card is 'totally free’, as all documentations are available, and all software is freeware which is needed for creation.

The purpose of the card is if at least the Z80 processor is working; it examines the memory, ULA and the ROM. It partly communicates on the screen, but when ULA is faulty, problem can de identified by the error codes of the LEDs. The PCB is optimized for homebrew finalization (hand drilling and welding). The size of Flash ROM can be between 128K and 512K. So we can burn inside anything with a help of a (working) Spectrum.

The aim of Spectranet Ethernet card is to put the Spectrum online again. This was realized in the past with the Prism VTX 5000 modem and Interface 1, as well with the RS-232 port. Unfortunately, these methods are out of dated now, so totally incompatibles.

The card is built around the WIZnet W5100 single-chip Ethernet device. This was specially designed for embedded 8 bit systems, so ideal for the Spectrum.

The controlling logic is done by a Xilinx XC9572 CPLD CPLD. 128K FlashROM and the same amount of RAM can be found n the board. First one can be programmed from the Spectrum, and various programmes can fit inside. The RAM is reserved for special programs, and also for general purposes.

This card is also can be reproduced homemade, and also a free, open project. During the planning, compatibility was a priority. So it works fine with all Sinclair and Amstrad models, and also with the Interface 1, DivIDE(+) and joystick interfaces.

Added: 2011. March 27.

48K composite video output

On Womble's Retro Repair Shack blog is published how to made a composite video output for the 48K (and thus for the 48k+) , which may interesting for a lot of owners.

The job takes up 10 minutes. What you need is a soldering iron and a 4cm wire. Anyway, another 10 minutes to reconstruct the original condition.

The trick is, that Speccy originally sends composite signals to the RF modulator, which is converted to RF signals. This is lead into the TV by the aerial cable, where the TV reconverts it to composite signals. This double lossy converting was necessary in the times of Spectrum, as TVs did not have separate AV input.

The advantage of Womble's picture illustrated modification -beside its simpleness- that it can be done without any psychical damage (drilling, extra screwing). By the way, the original documentation of this modification was released in a 1986 issue of Crash magazine.

SRAM replacement for lower 16k

In ZX Spectrum 48K(+) models the memory is divided into two parts. The upper 32K (2x4 ICs) is used solely by the Z80 CPU. The lower 16K (1x8 Ics) is shared between the ULA and the Z80. The errors of these chips often the cause of the non-working Spectrum.

How can the problem solved? It is seems simple, but there is a big problem. The 4116 DRAM memory ICs of Spectrum needs +5, +12 and -5V, and nowadays all available DRAMs work with simple +5V (the original DRAMs can not be bought as new).

So Alwin Henseler in 2009. February introduced the SRAM replacement for lower 16K modification, which is replacing the original chips with SRAM module. It has more advantage: first, it has lower consumption, which reduces the Speccy's heat output. And second, also fits fine into the place of the original chips.

The documentation gives detailed description of the modification as well the technical background. Alwin tested it with two types of SRAM chips, all of those were worked (in theory, all 70-150ns access time SRAM module will be fine). Testing machines were Issue 3B and 4B.

Added: 2010. július 10.

Click keyboard

The Italian Electrons beside his another modifications, also take care of the Spectrum. His Click keyboard modification is replacing the keyboard folie membrane with pushbuttons.

This mod is made 'forever' and from outside it is invisible. But while typing, the rubber keys will click under your fingers.

For realizing this modification, you need 40 pushbuttons, plus recommended to build also a reset button at the same time. First you have to take apart the Spectrum. Then you have to drill holes into the centre of the key places of the 'key box'. After you have to drill holes exactly into the same location into a rigid plate. Onto this plate, have to glue the pushbuttons, then also fill the gaps between them with glue for improving stability.

Wiring the pushbuttons to each others can be made by using the keyboard folie membrane as a template.

For last, you have to solder the original connectors to the end of 8+5 wires.

No more steps, put again together your machine.

Hozzáadva: 2010. július 15.

ZX Laptopok

Two ZX Spectrum laptops also saw the light, both of them are based on the 48K gummy version.

The laptop of srimech.com (Suburban engineering) was built on a Toshiba Libretto 110. The author was built in the gold old gummy keys, and the mainboard and screen remains from Toshiba. So, the main part of the work was to convert the Spectrum's 5x8 matrix to the laptop's 8x13 system. The computer is running Linux, so needed an emulator to feel like a real Spectrum.

Sami Vehmaa' machine is a real ZX laptop: the original machine with a 7" LCD screen, using Compact Flash card as mass storage device. On his website can access the DIY infos, and Sami can support LCD screens for request.

ZX Spectrum +128K

Richard Gellmann's ZX Spectrum +128K project is covers to made a homebrew ZX Laptop with LCD/TFT display, flat keyboard and modern storage devices.

The laptop is based on the ZX Spectrum +2 due its compatibility and nice features (such as RGB output).

The display is a 800x600 resultion TFT screen and .TZX files are stored on MMC card.

The computer will contain two custom chips. First one is ZX10701, which integrates the original ZX8401, PAL 10H8, 74174 and 74157 chips and also supports the NMI ROM.

Second is a ZX10702, which is a PIC16F627 microcontroller. The task of this to decode the signals of the PS/2 keyboard. It is used, because the PS/2 keyboard has numerous advantages comparing the original keyboard matrix. It is easy to replace and using the special keys (for example the multimedia buttons) is also a great feature.

Among the future plans there are a CMOS RAM/RTC and a mini LCD (date/time display, .TZX 'counter' etc.).

The file system is FAT16 and the FGPA-based VGA is a variant of Chris Smith's ULA clone.

Hozzáadva: 2010. július 26.

The Sinclair Shop

The Sinclair Shop is ran by Ian Priddey since 2004 and delivers to every part of the world.

Beside the Spectrum, offers ZX81 and QL accessories, even C64/128 and Amiga parts on sale. Of course, the parts of Amstrad designed Sinclair machines working well with the contemporary CPCs.

Most popular goods are the RGB Scart cables offered for all Spectrum models (thus these are manufactured in three subtypes).

Also spare parts in the warehouse: 48K tape lead, +2 tape and +3 drive belts, as well some types of transistors, diodes, plugs (serial, 9V DC, RGB Video, ZX edge connector). And there is +3 tape lead also.

The homepage is currently under development, presently we can do shopping through EBAY.

The German Sintech firm located Filderstadt lead by Thomas Eberle (EBI or FBI).

The on-line shop is handling new and retro computers, consoles and accessories. But the top of the hearth of Thomas there is the ZX Spectrum, which proven by the fact, he is the member of UVS (Users Vote Speccy) coding group and editor of the Scene+ tape and diskzine.

The Spectrum side of the shop offers relatively huge assortment. But it is only the surface, because a lot of goods are common stuff for the PC, Amiga and consoles.

Now pass round the specially ZX Spectrum accessories. Spare parts: TV antenna cable, 48/128K and +3 tape lead, and Scart-monitor cables for all types. Also there are power supplies for all Spectrums. The evergreen 48K and +/128K keyboard membranes offered too.

On the stock the internal and external versions of Proface AT. At the same way can be bought Spectrum keyword sticklers.

Sintech is still waiting for MB-03 pre-orders.

Some another tiny tots: video modulator for better picture quality, and an on/off switch between the Speccy and power supply.

DataServe Retro

DataServe Retro is a single person enterprise, which only handling 8 bit micros. Besides the buying-selling, also offering historical overview, and repairing and maintenance guides on the homepage.

This is a non-profit company. All items, which can be found here, fully restored and tested, so being in much better condition, than anywhere else we can search for.

Alongside of the used hardware, some new parts also available for the ZX Spectrum.

Certainly the 16/48K and 48K+/128K keyboard membranes are accessible. And can be bought the tape leads for these machines too.

Spare tape drive belt for all 128K+2 Spectrums, as well the 128K+3's drive belt can bought, and the tape leads for the last machine is also offered.

The TV antenna cable is fits for all Spectrum models, and also there is RGB Scart cable for 128K+2A/+2B/+3.

Thanks to buying up the old stock, some unused factory hardware is also available: 128K+2 and 128K+2A/+2B power supplies as well 3 inch floppies.

Clive.nl

In the 2003 founded Clive.nl primarily was created to put into circulation ZX Spectrum and another Sinclair goods. Later they extended the assortment with Acorn, Atari, BBC, Commodore, MSX, Schneider and Tandy hardware, software, book and magazine section.

In fact, it is a retro collecting group, which sells out the duplicates. The on-line ordered things are posted by priority airmail.

Above the used items, they have some new ones for the Spectrum mostly cables.

Informantica

The Informantica e-shop founded in 1999 besides supporting current platforms, also has offers for the fans of retro hardware.

In the case of Spectrum, it is the divIIDE+ interface, RGB cables suit for 128K+2 and +3 machines, as well the keyboard membranes of 16/48K, 48K+/128K.

Due to the Amstrad relationship, 128K+3 owners also shop their spare floppy drive belt and the ever rare 3" diskettes.

Some second hand Sinclair items also occur on the Ebay shop.

All Top Notch

All Top Notch is a small family run business manufacturing and selling audio-video cables and other accessories.

For the ZX Spectrum (and ZX81) also trading 2 and 4 meters long TV-cables.