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Didaktik Skalica Co. (Czechoslovakia) Sinclair ZX Spectrum Clone

June 11th, 2016 1 comment
Didaktik Skalica Co. (Czechoslovakia) ZX Spectrum Clone

A friend of mine left me some ZX Spectrum clones produced in the 90′s in Czechoslovakia and Russia.

As you can see from the photos i have tried to find the right pinout of the RGB video and audio output.

Thanks again Andrea Pierdomenico.

Gallery:

Bi Am (Russian) Sinclair ZX Spectrum 48-64 Clone

June 11th, 2016 No comments
Bi Am (Russian) ZX Spectrum 48-64

A friend of mine left me some ZX Spectrum clones produced in the 90′s in Czechoslovakia and Russia.

As you can see from the photos i have tried to find the right pinout of the RGB video and audio output.

Thanks again Andrea Pierdomenico.

Gallery:

Soviet LENINGRAD – Sinclair ZX Spectrum Clone

June 11th, 2016 No comments
1988 (Russian) ZX Spectrum Clone

A friend of mine left me some ZX Spectrum clones produced in the 90′s in Czechoslovakia and Russia.

As you can see from the photos i have tried to find the right pinout of the RGB video and audio output.

Thanks again Andrea Pierdomenico.

Gallery:

source: https://k1.spdns.de/Vintage/Sinclair/82/Clones/Russia/LENINGRAD/

Tulip Computers (CompuData) Tulip System 1

May 24th, 2016 1 comment
CompuData Tulip System 1

The Tulip system I was a 16-bit personal computer based on the Intel 8086 and made by Tulip Computers, formerly an import company for the Exidy Sorcerer, called CompuData Systems.

Its 6845-based video display controller could display 80×24 text in 8 different fonts for supporting different languages, including a (Videotex based) font for 2×3 pseudo graphic symbols for displaying 160×72 pixel graphics in text mode. The video display generator could also display graphics with a 384×288 or 768×288 (color) or 768×576 (monochrome) pixel resolution using its built-in NEC 7220 video display Coprocessor, which had hardware supported drawing functions, with a very advanced set of bit-block transfers, it could do line generating, arc, circle, ellipse, ellipse arc, filled arc, filled circle, filled ellipse, filled elliptical arc and many other varied commands.

Its memory could be upgraded in units of 128 KB up to 896 KB (much more than the 640 KB of the original PC).

It included a SASI hard disk interface (a predecessor of the SCSI-standard) and was optionally delivered with a 5 MB or 10 MB hard disk. The floppy disk size was 400 KB (10 sectors, instead of 8 or 9 with the IBM PC) or 800kb (80 tracks).

It ran at 8 MHz, almost twice the speed of the IBM PC XT which was launched only a few months earlier in July 1983. It had the possibility to use an 8087 coprocessor for math, which increased the speed to > 200 kflops, which was near mainframe data at that time.

After initially using CP/M-86 it quickly switched to using generic MS-DOS 2.00. There was a rudimentary IBM-BIOS-emulator, which allowed the user to use WordStar and a few other IBM-PC software, but Compudata B.V. shipped WordStar and some other software as adopted software for this computer. There was a programming support by Compudata B.V. with MS-Basic, MS-Pascal and MS-Fortran. On a private base, TeX and Turbo Pascal were ported to the Tulip System 1.

Gallery:

Works that i have made before power on the computer:

  • Removing the filter capacitor inside the power supply.
  • Replaced the tantalum capacitors.
  • Eprom (ROM) dump.
  • Found the pinout for the Video composite signal.
  • Cleaning.

Pinout for the Video composite:

Cleaning & Fix gallery:

Download:

source: wikipedia

Zenith Data System Monitor ZVM-122-EA (Amber Phosphor)

May 23rd, 2016 No comments
Zenith Data System Monitor ZVM-122-EA (Amber Phosphor)

Zenith Data Systems (ZDS) was a division of Zenith Electronics founded in 1979 after Zenith acquired Heathkit, which had, in 1977, entered the personal computer market.

Headquartered in Benton Harbor, Michigan, Zenith sold personal computers under both the Heath/Zenith and Zenith Data Systems names.

Gallery:

Sinclair Microvision MTV1B

April 6th, 2016 No comments

This is a Sinclair Microvision MTV1B. It’s the second attempt of Clive Sinclair’s to make a small portable television.

Released in 1978, it was the smallest television in the world with a CRT tube. A teeny-tiny 2″ D5-100w CRT made by Telefunken. Powered by 4 x AA or via External Powersupply at 6v DC (Negative at the center of the power connector).

Gallery:

Download: Sinclair Microvision MTV1B Schematics (1261)

Luxor ABC 80 (Boxed)

April 6th, 2016 5 comments

The ABC 80 (Advanced BASIC Computer 80) was a home computer engineered by the Swedish corporation Dataindustrier AB (DIAB) and manufactured by Luxor in Motala, Sweden in the late 1970s (first model August 1978) and early 1980s. It was based on the Zilog Z80 running at 3 MHz and had 16 KB RAM, expandable to 32 KB, and 16 KB ROM containing a fast semi-compiling BASIC interpreter.

ABC 80 normally used a dedicated (included) tape recorder for program and data storage, but could also be expanded to handle disk drives (and many other peripherals). Some sound effects could be produced by a Texas Instruments SN76477 sound chip which was connected to an 8-bit output port, but there was no way to control the chip’s features in any detail, so sound was limited to 96 fixed sounds. The monitor was a black and white TV set modified for the purpose (an obvious choice since Luxor also made TVs). The computer had excellent I/O response times, something that was discovered when trying to upgrade to personal computers. The solution was to use a microcontroller that communicated with a PC. The main unit had a reset button as well.

ABC 80 was also manufactured on license as BRG ABC80 by Budapesti Rádiótechnikai Gyár in Hungary. It used the same keyboard, but the case was metal instead of plastic.

The ABC 80 was a huge hit in Sweden, and grasped a majority share of the rising personal computer market thanks to its office software in Swedish. Although the ABC 80 fans would defend the ABC 80 by referring to its good BASIC and usable extension bus, it couldn’t defend the home market against the gaming computers with color graphics and better sound that arrived in the early 80s like the Commodore 64, even though a new cheaper version was released that could use an ordinary TV instead of the dedicated video-monitor.

Luxor held on to its office market for a couple of years longer with the ABC 800 series, which had a more extensive BASIC, more memory and a 512×240 ‘high-resolution’ graphics mode, but otherwise similar performance. In 1985 Luxor also tried to compete in the office market against the IBM PC with its ill-fated ABC 1600 and ABC 9000 series UNIX computers, but failed.

Gallery:

… and the boxes

Software

source: wikipedia

Commodore CBM 4008

April 5th, 2016 No comments
Commodore CBM 4008

The Commodore PET 4000 series features Basic 4.0 as a standard feature, along with more memory and a lower price that made them attractive to schools.

Elementary, Middle, and High Schools all over Canada and the United States were filled with these impressive lumbering beasts. Introducing children far and wide to the wonders of BASIC programming. Another lesson taught was the importance of patience, since many schools provided only a tape datasette for loading and saving work.

Like the other models of PET, the 4000 series includes dual datasette ports, though only one is exposed to the outside of the casing. A standard IEEE-488 interface in the back allows the PET to connect to the numerous (and heavy) disk drives and printers being produced by Commodore and other manufacturers.

The PET also has a fully programmable bi-directional parallel interface called the “User” port, which allows the PET to connect and control almost any device one could dream up! The greatest feature, however, is the friendly READY prompt, and the well-laid out keyboard with graphic characters only a keypress away! Pictured here is the PET 4016.

Interestingly, although Commodore provided 8, 16, and 32k versions of their PET 2001 and 3001 series, they had a hard time getting people to purchase higher memory versions as an upgrade. It seemed that people were soldering in their own memory chips onto PET 2001 and 3001 8k and 16k models to upgrade them to 32k. To help prevent this, Commodore sold many PET 4008 and PET 4016 models with the empty memory sockets punched out and destroyed! This encouraged those who wanted more memory to upgrade to the 4032 instead of doing it themselves.

Gallery:

source: zimmers.net

C4CPC cartridge replacement for the Amstrad Plus range & GX4000

April 5th, 2016 1 comment
C4CPC cartridge replacement for the Amstrad Plus range and the GX4000

C4CPC is a cartridge replacement for the Amstrad Plus range and the GX4000.

Using a micro-SD card storing cartridge images it also allows direct loading of the cartridge from a PC (Windows/Linux/OSX) through USB.

Features:

  • Direct access to 16 cartridges selected by dip switches. Cartridge can be up to 512kB.
  • Access to unlimited number of cartridge images using the provided selector cartridge.
  • Direct cartridge loading from host computer using USB.
  • Cartridge file can be in standard .cpr format or raw binary .bin
  • Integrated ACID.

Gallery:

Download: C4CPC GX4000 microSD Games & Demos (1214)

source: cpcwiki.eu

Commodore SX-64 USA (NTSC) – Repairing and Cleaning

April 5th, 2016 1 comment
Commodore SX-64 (USA)

A big disappointing this Commodore SX-64 USA purchased for spare parts to fix aesthetically one of my SX-64 PAL.

Why disappointing? because from the photo’s looked in a very bad shape, rust stains, various diseases and not working.

Conversely after removed the shit from the external case, replaced the booring PLA (906114), general cleaning + keyboard / Floppy Drive test and replaced one keyboard lock, the SX-64 is fully working and aesthetically in good condition.

Now i have for myself four SX-64 where the fourth is NTSC/USA, but honestly i was not looking for the USA version.

I am really unlucky :D

Gallery of the cleaning and repairing:

Australian Commodore 64 (replacement case for the C64)

February 16th, 2016 7 comments
Commodore 64 Australian (Original Color - not Photoshopped)

The Commodore 64 Australian is an replacement case for the C64.

It’s an C64c look-a-like and was sold in Australia. This replacement case came on the market when Commodore introduced it’s new model, the C64C.

Gallery:

Testing ICE Felix HC-90 (ZX Spectrum Clone) for a friend

January 25th, 2016 1 comment
I.C.E. Felix HC-90 (ZX Spectrum Clone)

Testing ICE Felix HC-90 (ZX Spectrum Clone) for a friend.

This is a series of ZX Spectrum clones was manufactured in Romania from 1985 to 1994, by ICE Felix. The designation HC means Home Computer, and for the first three models in the series, the number is the year of first manufacture. Models in the series were: HC 85, HC 88, HC 90, HC 91, HC91+ (HC128), HC 2000, HC386.

The earliest version, HC 85, closely resembled the Spectrum, with a built-in BASIC interpreter, Z80A processor, 48 KB RAM, tape, and TV interfaces. It was used in schools/universities and as a personal computer.

An optional Interface 1 extension was available for the HC 85, HC 90, and HC 91. It was functionally similar to the ZX Interface 1, but instead of Microdrives it supported single-density or double-density floppy disks. The HC 90 had a redesigned circuit board supporting fewer, larger memory chips; it was functionally equivalent with the HC 85.

The HC 91 had a modified keyboard with 50 keys instead of 40. It had 64 KB RAM and extra circuitry which provided CP/M support, if the Interface 1 extension was also present.

The HC 2000 (manufactured from 1992–94) had a built-in 3.5-inch 720 KB disk, and 64 KB RAM, it could be used both as a Spectrum clone with added disk functionality (only 48 KB RAM available) or in CP/M mode, giving access to the full 64 KB memory. Essentially, it brought the HC 91, Interface 1, and floppy disk in a single case.

The last model to be made in the Z80 line was the HC91+. It was a ZX Spectrum 128K clone in a HC91 case and keyboard and had some compatibility problems. For the first time, the AY-8910 sound chip was offered as an add-on service and was soldered on the board by factory technicians. Demoscene demos had problems running multi-colour effects and displaying sound VU-meter like effects lacking some data from the AY chip probably.

Gallery:

source: wikipedia

MicroTech – SpaceMaker II

January 6th, 2016 No comments

In the Commodore Pets and CBMs, ROM expansion area is available in empty sockets on the main logic board. These sockets are addressed as 4K byte blocks and are used by many of the software packages available for Pet and CBM!.

These include the Commodore Word Processors, the BPI business package, VISICALC from Personal Software, Inc., Rabbit from Eastern House Software, BASIC Programmers TOOLKIT from Palo Alto ICs, Sort from Matric Software, Inc., and many others.

Several of these ROMs are to be installed in the same ROM socket within the Pet. Spacemaker II is a utility device which allows switching of up to four ROMs into any socket from a single board. Since Spacemaker II is jumper programmable for each of its four ROM sockets.

ROM type may be different for each socket. Switching can be done with a side mounted switch or via ROM DRIVER, an accessory device which allows software and keyboard control of ROM selection.

Spacemaker II is also available for changing character sets with Math or Foreign language ROMs available from West River Electronics.

Gallery:

Download: MicroTech - SpaceMaker II Manual (996)

Commodore 64c Embossed Label

January 4th, 2016 No comments
Commodore 64c Embossed Label

This is the latest version of C64c and was cost reduced even more.

Instead of a metal plate on the top there is the logo only engarved in plastic case itself.

The keyboard has been held on the upper housing part with brackets (not with screws as normal). In addition, the housing itself was only held together with clamps.

Gallery:

source: scacom.bplaced.net/Collection/64/

Commodore-MOS KIM-1

December 19th, 2015 1 comment

The KIM-1, short for Keyboard Input Monitor, was a small 6502-based single-board computer developed and produced by MOS Technology, Inc. and launched in 1976. It was very successful in that period, due to its low price (following from the inexpensive 6502) and easy-access expandability.

The KIM-1 consisted of a single printed circuit board with all the components on one side. It included three main ICs; the MCS6502 CPU, and two MCS6530 Peripheral Interface/Memory Devices. Each MCS6530 comprises a mask programmable 1024 x 8 ROM, a 64 x 8 RAM, two 8 bit bi-directional ports, and a programmable interval timer. The KIM-1 brochure said “1 K BYTE RAM” but it actually had 1152 bytes. The memory was composed of eight 6102 static RAMs(1024 x 1 bits) and the two 64 byte RAMs of the MCS6530s. In the 1970s memory sizes were expressed in several ways. Semiconductor manufacturers would use a precise memory size such as 2048 by 8 and sometimes state the number of bits (16384). Mini and mainframe computers had various memory widths (8 bits to over 36 bits) so manufacturers would use the term “words”, such as 4K words. The early hobbyist computer advertisements would use both “words” and “bytes”. It was common to see “4096 words”, “4K (4096) words” and “4 K bytes”. The term KB was unused or very uncommon. The KIM-1 was introduced in the April 1976 issue of Byte magazine and the advertisement stated “1 K BYTE RAM” and “2048 ROM BYTES”.

Also included were six 7-segment LEDs (similar to those on a pocket calculator) and a 24-key calculator-type keypad. Many of the pins of the I/O portions of the 6530s were connected to two connectors on the edge of the board, where they could be used as a serial system for driving a Teletype Model 33 ASR and paper tape reader/punch).

One of these connectors also doubled as the power supply connector, and included analog lines that could be attached to a cassette tape recorder.

Earlier microcomputer systems such as the MITS Altair used a series of switches on the front of the machine to enter data. In order to do anything useful, the user had to enter a small program known as the “bootstrap loader” into the machine using these switches, a process known as booting. Once loaded, the loader would be used to load a larger program off a storage device like a paper tape reader. It would often take upwards of five minutes to load the tiny program into memory, and a single error while flipping the switches meant that the bootstrap loader would crash the machine. This could render some of the bootstrap code garbled, in which case the programmer had to reenter the whole thing and start all over again.

The KIM-1 included a somewhat more complex built-in Terminal Interface Monitor software called TIM that was “contained in 2048 bytes of ROM in two 6530 ROM/RAM/IO arrays”. This monitor software included the ability to run a cassette tape for storage, drive the LED display, and run the keypad. As soon as the power was turned on, the monitor would run and the user could immediately start interacting with the machine via the keypad. The KIM-1 was one of the first single-board computers, needing only an external power supply to enable its use as a stand-alone experimental computer. This fact, plus the relatively low cost of getting started, made it quite popular with hobbyists through the late 1970s.

Gallery:

Download: Commodore-MOS KIM-1 Docs (1083)

 source: wikipedia