Autopsy:

Here you can see a hack of my dtv (Direct-to-TV).

from Wikipedia:

The C64 Direct-to-TV, called C64DTV for short, is a single-chip implementation of the Commodore 64 computer, contained in a joystick (modeled after the mid 1980s Competition Pro joystick) with 30 built-in games. The design is similar to the Atari Classics 10-in-1 TV Game. The circuitry of the C64DTV was designed by Jeri Ellsworth, a self-taught computer chip designer who had formerly designed the C-One.

Tulip Computers (which had acquired the Commodore brand name in 1997) licensed the rights to Ironstone Partners, which cooperated with DC Studios, Mammoth Toys, and “The Toy:Lobster Company” in the development and marketing of the unit.[1] QVC purchased the entire first production run of 250,000 units and sold 70,000 of them the first day they were offered.

There exist multiple versions of the C64DTV. DTV1 (NTSC television type) comes with 2 MB ROM. It first appeared in late 2004 for the American/Canadian market. DTV2 (called C64D2TV sometimes) is a revised version for the European and world markets (PAL television type) and appeared in late 2005. The ROM has been replaced by flash memory in these devices. However, the DTV2/PAL version suffers from a manufacturing fault, which results in poor colour rendering (the resistors in the R-2R ladder DACs for both the chroma and the luma have been transposed). In the DTV3, a problem with the blitter was fixed. Another DTV variant is the Radio Shack “HUMMER Off-Road Racing Challenge Video Game”.

Hardware Specifications:

Core circuity:

• ASIC running at 32 MHz internally, implementing 6510 CPU, VIC-II, SID, CIA, and PLA

Casing/Connectors:

• Integrated in a Joystick (as if connected to port 2 of a real C64)
• Five additional buttons (acting like keys)
• Running from batteries only (four AA batteries)
• Composite Video, monaural audio (RCA connectors)
• Looks similar to a Competition Pro joystick

Graphics:

• NTSC (DTV2 and later: NTSC/PAL on chip, only PAL wired in end-market devices)
• Reprogrammable palette with 4 bits of luma and 4 bits of chroma
• DTV2 and later: “chunky” 256 color mode, additional blitter for fast image transformation

Sound:

• No support for SID filters
• DTV2 and later: 8 bit digital sound, additional options for envelope generators

Memory:   

• DTV1: 128 KB RAM, 2 MB ROM
• DTV2 and later: 2 MB RAM, 2 MB flash memory
• DMA engine for RAM/RAM and ROM/RAM transfers
• DTV2 and later: additional RAM access using bank switching and blitter

CPU:

• Implementing a 6510 at 1 MHz
• DTV2 and later: Enhanced CPU (fast/burst mode, additional registers and opcodes, support for illegal ops of the 6510)

source: wikipedia dtvhacking.retrosafe.com

Autopsy:

The Expandamem of CompuThink (Compu/Think) is a Memory expansion card for Commodore PET (chicklet keyboard) and KIM-1.

The memory expansion was installed inside the Computer Commodore PET and with a particular hook was fixed above the motherboard. The connection was through the expansion bus and a power connector.

Download: CompuThink Memory Expansion Manual (1664)

Autopsy:

The Analog Joystick by Pico Products is a compatible Joystick with Apple and IBM AT/XT PC.

Specifications:

• Quickfire button on sitck.
• User Selectable Auto-Centering or Free-Floating Operating Modes.
• Right and Left hand function with firing Buttons.
• Dual Axis Vatiable Resistor Controls for Accurate and Stable Cursor control.
• Apple II,II+,IIc,IIgs and IBM PC,AT,XT compatible.

I thank a friend for the donation.

Donated items:

• Hardital (Italy) Bang 2082.
  • This is a Accelerator expansion for Amiga 500/2000 with a 68020 @ 14.3 MHz (synchronous) and a optional FPU up to 68882 @ 25 MHz (asynchronous).

• Logica (Italy) Kick Mouse.
  • Kickstart Switcher 2.0

Autopsy:

from Zimmers homepage:

The Commodore 1600 was an extremely prolific and inexpensive modem, introducing millions of computer users to the online world. Marketed to the VIC-20 user, the “VICMODEM” as it was nicnamed, operated in an extremely strange manner.

Instead of connecting to the phone line directly, the VICMODEM relied on a connection THROUGH the phone to the handset. One would dial the number they wished to connect to, then remove the extension from their handset, plugging it into the modem after a carrier signal is heard.

Some customers in Canada were lucky enough to get their VICMODEM packaged with this telephone manufactured in Canada by Northern Telecom. Ironically, the phone did not have a detachable handset, making it useless by itself for use with the modem. Therefore, the set also included a small adaptor which allowed one to plug the VICMODEM directly into the wall line cable, daisy chained to the phone. After dialing with the phone, a switch on the adaptor would redirect the carrier signal to the modem.

Download: Commodore VIC Modem Model 1600 Manual (1719)

source: zimmers.net

Autopsy:

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from Wikipedia:

The Amstrad CPC (short for Colour Personal Computer) is a series of 8-bit home computers produced by Amstrad between 1984 and 1990. It was designed to compete in the mid-1980s home computer market dominated by the Commodore 64 and the Sinclair ZX Spectrum, where it successfully established itself primarily in the United Kingdom, France, Spain, and the German-speaking parts of Europe.

The series spawned a total of six distinct models: The CPC464, CPC664, and CPC6128 were highly successful competitors in the European home computer market. The later plus models, 464plus and 6128plus, efforts to prolong the system’s lifecycle with hardware updates, were considerably less successful, as was the attempt to repackage the plus hardware into a game console as the GX4000.

The CPC models’ hardware is based on the Zilog Z80A CPU, complemented with either 64 or 128 kB of memory. Their computer-in-a-keyboard design prominently features an integrated storage device, either a compact cassette deck or 3″ floppy disk drive. The main units were only sold bundled with a colour or monochrome monitor that doubles as the main unit’s power supply. Additionally, a wide range of first and third party hardware extensions such as external disk drives, printers, and memory extensions, was available.

The CPC series was pitched against other home computers primarily used to play video games and enjoyed a strong supply of game software. The comparatively low price for a complete computer system with dedicated monitor, its high resolution monochrome text and graphic capabilities and the possibility to run CP/M software also rendered the system attractive for business users, which was reflected by a wide selection of application software.

During its lifetime, the CPC series sold approximately three million units.

Cleaning / Replacement of the little rubber, reconstruction of pitches with a soft pencil:

source: wikipedia cpcwiki.eu

The composite video mod for the computer Microdigital TK-83 unlike the Sinclair ZX81 it’s more easier.

You no need to install the usual transistor with 1 or 2 resistors / capacitor. The transistor is already installed on the motherboard of the Microdigital TK-83, so just pick up the video signal as described in the picture.

I remind you that the output signal will be in NTSC standard for the Microdigital TK-83 produced in Brazil (PAL-M)

Autopsy:

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from Wikipedia:

TK83 was a Sinclair ZX81 clone made by Microdigital Eletrônica Ltda., a computer company located in Brazil.

The TK83 had the ZILOG Z80A processor running at 3.25 MHz, 2 KB SRAM expandable up to 64 KB and 8 KB of ROM with the BASIC interpreter and a Joystick port. The keyboard was made of layers of conductive (membrane) material and followed the Sinclair pattern. The video output was sent via a RF modulator to a TV set tuned at VHF channel 3, and it featured black characters on a white background. The maximum resolution was 64 x 44 pixels black and white, for graphic plotting. There were some special characters (shade patterns) useful for games and basic images.

Although being a ZX81 clone, the TK83 did not have the ULA chip from Ferranti, used in the former. Instead it was manufactured with a dozen of TTL integrated circuits, which resulted in a somewhat large power consumption. This could be noted as the computer’s case used to become quite hot after some minutes of operation.

source: wikipedia

Autopsy:

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from Wikipedia:

The Amstrad CPC (short for Colour Personal Computer) is a series of 8-bit home computers produced by Amstrad between 1984 and 1990. It was designed to compete in the mid-1980s home computer market dominated by the Commodore 64 and the Sinclair ZX Spectrum, where it successfully established itself primarily in the United Kingdom, France, Spain, and the German-speaking parts of Europe.

The series spawned a total of six distinct models: The CPC464, CPC664, and CPC6128 were highly successful competitors in the European home computer market. The later plus models, 464plus and 6128plus, efforts to prolong the system’s lifecycle with hardware updates, were considerably less successful, as was the attempt to repackage the plus hardware into a game console as the GX4000.

The CPC models’ hardware is based on the Zilog Z80A CPU, complemented with either 64 or 128 kB of memory. Their computer-in-a-keyboard design prominently features an integrated storage device, either a compact cassette deck or 3″ floppy disk drive. The main units were only sold bundled with a colour or monochrome monitor that doubles as the main unit’s power supply. Additionally, a wide range of first and third party hardware extensions such as external disk drives, printers, and memory extensions, was available.

The CPC series was pitched against other home computers primarily used to play video games and enjoyed a strong supply of game software. The comparatively low price for a complete computer system with dedicated monitor, its high resolution monochrome text and graphic capabilities and the possibility to run CP/M software also rendered the system attractive for business users, which was reflected by a wide selection of application software.

During its lifetime, the CPC series sold approximately three million units.

Replacement/Adaptation of a power switch for Amstrad CPC 464:

source: wikipedia cpcwiki.eu

I have decided to replace my Amiga 1000 keyboard (US version) with the space key yellowed and a hole in the plastic caused by a wrong installation with a Amiga 1000 keyboard (Italian version) cosmetically perfect and running.

I bought a few things from the site Retro Innovations of Jim Brain.

6540 Rom Adapter:

• This PCB converts the MOS 6540 DIP pinout to a JEDEC standard 2764-27512 EPROM pinout.  The optional 5 upper address lines are available via pads complete with provision for pullup resistors (10K).

Commodore IEC Disk Drive Cable:

• This very short cable is useful for my second Ultimate 1541.

Autopsy:

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The Genius PC is a home computer from VTech. Released in the late 90s, it is one of the last microcomputers.

This computer have different names in each country, making it even harder to track down the information.

• France : VTech Genius PC
• Germany : VTech Genius IQ 128 and VTech TV 512
• UK : VTech IT Unlimited
• USA : VTech Precomputer Unlimited
• Also mentioned on the french packaging : Switzerland, the Netherlands, Canada.

Hardware:

• Motorola MC68EC000, 16-bit external databus, 32MHz
• 256K of RAM
• 2M of ROM – Sharp LH537NWN mask ROM
• Mass storage : 128KB flash memory – AM29F010
• Cartridge port, apparently on memory bus with system ROM and storage flash. The french system comes with cartridges only containing straps, likely shorting some pins enable extra features…

Downlod: VTECH Unlimited Manual (1617)

Hardware Video Review:

source: pulkomandy.tk/projects/avrstuff/wiki/geniuspc

Autopsy:

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I have removed the main filter capacitor of 0,47μF 250v (RIFA), avoiding that can explode.

from Wikipedia:

The Apple Monitor // was a CRT-based green monochrome 12-inch monitor manufactured by Apple Computer for the Apple II personal computer family. Apple didn’t manufacture the monitor until halfway through the lifespan of the II series.

The business-line Apple /// had its own Apple Monitor /// long before. Many home users of Apple II computers used their televisions as computer monitors before the Monitor // was released. It featured an inner vertical-swiveling frame. This allowed users to adjust the viewing angle up or down to suit their taste without the addition of a tilt-and-swivel device.

The Monitor // was widely adjustable for the time, as it included adjustments for the size and location of the image on the screen. These adjustments had a very small influence on the picture, however, much to the disliking of some users. The Monitor // was designed for the Apple II+, but was used widely throughout the Apple II product line, most recognizably on the Apple IIe.

Download:

• Apple Monitor II User\'s Manual (1492)
• Apple Monitor II Circuit Diagram (462)

source: wikipedia

Autopsy:

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This is the translation of the Arabic boot screen:

© 1987, 1988 Sinclair of Egypt
presented by Matsico Corp, an authorized dealer of Sinclair & Amstrad in Egypt
prepared by Dr. Nabil Nazmi
(Version 3)

The computer is arrived in pitiful condition. The inside of the computer and the keyboard were are full of sand and dirt.

Restoration and repairs that have been made:

• Replaced the top case with a new one.
• Replaced the bottom case with a new one, then replaced again with the old one to keep the original appearance. (the hole for the switch is standard in the Arabic version)
• Replaced the tape recorder.
• Replaced the motherboard with a issue #2 instead of issue #1 (was not convenient the repair)
• Cleaned all keys and membrane.
• Replaced all rusty springs of the keyboard.
• General cleaning.
• Moved the ROM/EPROM mod on the new motherboard.
• Replaced the original switch with a new one, then replaced again with the old one to keep the original appearance.

from Wikipedia:

The ZX Spectrum +2 was Amstrad’s first Spectrum, coming shortly after their purchase of the Spectrum range and “Sinclair” brand in 1986. The machine featured an all-new grey case featuring a spring-loaded keyboard, dual joystick ports, and a built-in cassette recorder dubbed the “Datacorder” (like the Amstrad CPC 464), but was in most respects identical to the ZX Spectrum 128. The main menu screen lacked the Spectrum 128′s “Tape Test” option, and the ROM was altered to account for a new 1986 Amstrad copyright message. These changes resulted in minor incompatibility problems with software that accessed ROM routines at certain addresses. Production costs had been reduced and the retail price dropped to £139–£149.

The new keyboard did not include the BASIC keyword markings that were found on earlier Spectrums, except for the keywords LOAD, CODE and RUN which were useful for loading software. This was not a major issue however, as the +2 boasted a menu system, almost identical to the ZX Spectrum 128, where one could switch between 48k BASIC programming with the keywords, and 128k BASIC programming in which all words (keywords and otherwise) must be typed out in full (although the keywords are still stored internally as one character each). Despite these changes, the layout remained identical to that of the 128. The ZX Spectrum +2 power supply was a grey version of the ZX Spectrum+ and 128 power supply.

The ZX Spectrum +2A was a variant of the Spectrum +3 housed a black version of the Spectrum +2 case mouldings. The Spectrum +2A/+3 motherboard (AMSTRAD part number Z70830) was designed such that it could be assembled without the floppy disk controller or associated logic and a +2 style “datacorder” connected. Originally, Amstrad planned to introduce an additional disk interface for the +2A/+2B called the AMSTRAD SI-1, however this never appeared. If an external disk drive was added, the “+2A” on the system OS menu would change to a +3.

The power supply of the ZX Spectrum +2A used the same pinout as the +3. However, the power supply purchased with the +2A/B had “Sinclair +2″ written on the case.

source: wikipedia