The failure was due to a cold solder on the ram socket and a bent pin on the ic MOS 8276.

Autopsy:

Donated By: Andrea Pierdomenico

from Wikipedia:

Commodore’s RAM Expansion Unit (REU) range of external RAM add-ons for their Commodore 64/128 home computers was announced at the same time as the C128. The REUs came in three models, initially the 1700 (128 KB) and 1750 (512 kB), and later the 1764 (256 kB, for the C64).

Although the C128 could access more than 64 kB of RAM through bank switching, the memory inside the REU could only be accessed by memory-transfers (STORE/LOAD/SWAP/COMPAREs) between the main memory and the REU memory, thus, giving an equivalent to a (slow) small memory window. Additionally, the C128′s built-in BASIC 7.0 had three statements, STASH,FETCH, and SWAP, for storing and retrieving data from the REU.

Officially, only the 1700 and 1750 were supported on the C128. The 256 kB model, the 1764, was released for the C64 at the same time. However, aside from a bundled 2.5 ampere C64 power supply unit (the factory unit could not support the 1764), there were only minor differences between the three models.

In practice, the difference between the 1764 and the earlier units had little effect on compatibility, and people used 1700s and 1750s successfully with the C64, and 1764s successfully with the C128, although the C64′s stock power supply was inadequate to reliably handle the power load of any of them. Some dealers unbundled the 1764 and the power supply in order to sell the power supply to C64 users, and/or upgrade the 1764 to 512 kB.

Because of memory chip shortages in the late 1980s, the 1750 was only produced in small quantities. However it was not difficult to upgrade a 1700 or 1764 to 512 kB. Several firms did this commercially, either selling upgraded units or upgrading customer-supplied units.

In the early 1990s, DIY modification schemes to increase the capacity of an REU to one megabyte or higher appeared on various online services.

source: wikipedia

Some Commodore 64 in bad state (not working) for Spare Parts.

Javatari is a multiplayer Atari 2600 emulator written in pure Java with no external libs.

Features:

• Client-Server multiplayer mode. Runs great in low-latency networks such as LANs.
• Drag&Drop and Copy&Paste of ROM files or URLs. Very easy to try ROMs from websites!
• Scanlines and TV screen emulation modes.
• Real Atari console user interface.

Changelog;

• Applets can now be detached from the browser window.
• Once detached, all features are available including Full Screen.
• Full Screen is now multi-monitor aware.
• Updated, cleaner looks.

Download: Javatari JAR v3.30 (Needs Java 6) (955)

source: javatari.org

This power supply for the REU 1764 is arrived for repair destroyed, the internal transformer was completely extirpated from the pcb.

Autopsy:

12►

This is a clone of the famous Kupke Golem RAM Box for Commodore Amiga 1000.

The Kupke Golem RAM Box was very expensive at the time but it was also one of the few memory expansions with a pass through for the Commodore Amiga 1000.

source: amiga.resource.cx

I have disabled the mod to make the screen in reverse (white chars on black background), i have also made the composite mod with the right resistor value for the best quality video output.

Autopsy:

1234►

Donated By: Andrea Pierdomenico

Mini Floppy Disk Drive for the Sharp PC-5000 (compatible MZ-800 through the interface MZ-1E05)

The Sharp Mini Floppy Disk Drive CE-510F is a double-density, double-sided 5 1/4 unit with a capacity of 320K per disk. The drive, of course, must be operated with AC power and is not portable.

The Sharp MZ-1E05 Interface is a Floppy Disk Card for MZ-700/MZ-800.

Download:

• Sharp MZ-1E05 Service Manual (1737)

Sharp MZ-800 Booting Disk Basic from Floppy Disk Drive:

Replacement:

12►

Simple steps to replace the keyboard Membrane of the Sinclair ZX Spectrum 128k (heatsink).

• Buy a new Sinclair Spectrum 128k Keyboard membrane.
• Unscrew the eight screws on the bottom.
• Kindly disconnect the keyboard from the connectors on the main pcb.
• Remove the back of the keyboard.
• Unscrew the block that holds the cable.
• Remove the old membrane.
• Clean the keyboard with air-spray and a soft brush.
• Install the new membrane.
• Close the back of the keyboard.
• Very kindly put the block of the flat cable and screw in.
• The keyboard is ready to be connected.
• Very kindly insert the flat cable into the connector.
• Your Sinclair ZX Spectrum 128k is like new.

source: rwapsoftware.co.uk

I thank my dear friend for the donation of the Cartridges for Commodore VIC-20.

I thank my dear friend for the donation of the BASIC cartridge for my Sega SC-3000.

I thank my dear friend for having found the original power supply of my Sinclair ZX80.

I thank my dear friend for the donation of the motherboards.

• Commodore Dual Drive Floppy Disk CBM 8250
• Commodore CBM 8296

Some new games (Cracked / Trained or Unrealeased) for Commodore 64 have been released from your favorites groups:  TRIAD, Hokuto Force, The Hidden Farts and Laxity.

Download:

• Danger Valley +2ED (1029)
• Guardian HS (970)
• Ballistix (AMIGA REMIX) +4FGD [pal/ntsc] (963)
• Ponk (962)
• War in Space (Krieg im W.) +3EFD [pal/ntsc] (992)
• All Games in One Archive (2401)

source: csdb.dk

A dear friend sent to me a few things to repair or test, i will see to do my best.

Things to repair/testing:

• Commodore 64/128 – 1764 Ram Expansion (dead)
• Commodore 64 Power Supply for the Commodore 1764 Ram Expansion (pcb broken)
• ZX Spectrum Plus (7805 over burned)
• Texas Instruments TI-99/A (black screen)
• Amstrad 464 + (replace case and keyboard)
• Kung-fu Master Jamma pcb Board (no audio)
• Arabian Sinclair Spectrum 2+ (dead + tape problem + keyboard problem)
• Sinclair ZX81 (video problem / testing)
• Sinclair ZX80 (video problem / testing)
• Sega SC-3000 (cpu bad socket)

Things for spare parts or to keep:

• Sinclair ZX80 Original Power Supply.
• Commodore VIC-20 Boxed cartridges.
• Sega SC-3000 Basic cartridge.
• Commodore Dual Floppy Drive 8250 motherboard (spare parts)
• Commodore CBM 8296 motherboard (spare parts)
• Sharp CE-510F Dual Floppy Drive for Sharp PC-5000 (Boxed)
• Chalkboard Powerpad + Expansions (Boxed)
• Tape Recorder for Commodore (spare parts)