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Spare parts for Commodore 64, ZX Spectrum and more!

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C64 Modifications

Misc items for modifying C64 PCBs..

Products:

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8K / 4K 24-pin switchable ROM replacement module

Replaces 24-pin 8K (and 4K*) ROMs that have the standard EPROM pin out (eg: TMS 4764) and an active low output select pin, such as the breadbin C64's Kernal, BASIC and Character ROMs
Has an onboad switch allowing two different ROM images to be selected, if desired.
Uses a very low power modern EEPROM chip.
Please email me the ROM images you require on the module after purchase.
Note: The module cannot be reprogrammed in a standard EPROM burner as it requires a special interface to set up.

* Regarding 4K ROMs: As long as pin 21 on the PCB taking a 4K ROM is tied high or low (ie: not left floating) no PCB modification is required (and if it is floating, just connect it to pin 24 or pin 12 - either is fine). (In the breadbin C64, the Character ROM (U5) is 4K, and pin 21 is pulled low already on the PCB. The BASIC (U3) and KERNAL (U4) ROMs are 8K.

3 Metres of Kynar-style PCB repair wire

Fine (0.25mm solid core) wire, useful for repairing damaged PCBs
Sold in 3 Metre lengths
Colour: Green

De-solder Braid / Wick (1.5 Metres x 2.5mm)

Ideal for assisting repair work on motherboards etc
Sold in sealed packs.

Flux Pen

Helps solder flow cleanly, ideal for re-work jobs etc
Will also dissolve old flux residue etc to prepare very clean solder pads.
Non-corrosive flux.
Contents: 10ml

Small Tube Of Thermally Conductive Adhesive

For attaching heatsinks to chips
5 gram tube - enough for about a dozen chips
Instructions supplied

Heatsink for 24 pin DIL Chips - Black Anodized, Bare

Heatsink for 24 Pin DIL Chips - Bare

Heatsink suitable for 24 PIN Chips such as the ROMs in Commodore 64.
Black anodized finish
Dimensions: 33mm x 19mm x 4.8mm
Attachment methods: The heatsink is not self-adhesive - it requires thermally conductive glue which I sell separately.

Heatsink for 24 pin DIL Chips - Black Anodized, Self-Adhesive

Heatsink for 24 Pin DIL Chips - Self-Adhesive

As above but with self-adhesive backing tape, ready to apply to chip.

Heatsink for 40 pin DIL Chips - Black Anodized, Bare

Heatsink for 40 Pin DIL Chips - Bare

Heatsink suitable for 40 PIN Chips such as the CPU in the Commodore 64 and ULA in ZX81 and Spectrum Plus.
Note: There is not enough room for a heatsink in the rubber-keyed Spectrum unless you desolder the ULA's IC socket and fit the ULA directly onto the motherboard. For the Spectrum+ there is room to fit the heatsink without soldering the ULA to the PCB if the keyboard backing plate is the thin grey metal type (the plastic backing plates are thicker and get in the way slightly).
Black anodized finish
Dimensions: 50mm x 19mm x 4.8mm
Attachment methods: The heatsink is not self-adhesive - it requires thermally conductive glue which I sell separately.

Heatsink for 40 pin DIL Chips - Black Anodized, Self Adhesive

Heatsink for 40 Pin DIL Chips - Self Adhesive

As above, but with thermally-conductive self-adhesive pad pre-attached, ready to peel and apply.

Large Tesa brand isopropyl alcohol wipe

Large (folds out to approx 14x18cm) 70% Isopropyl alcohol wipe
Suitable for cleaning contacts, chips/heatsinks etc
Made by Tesa, the adhesive specialists

Restore key mod capacitor - axial type 4.7nf

Restore key mod capacitor for Breadbin C64 - Axial type

It has been found that replacing C38 with a 4.7nf capacitor improves the response of the restore key, ie: when modded, pressing RunStop+Restore should respond with the same pressure as any other key.
This is an axial type capacitor (wire at each end of cylindrical body, the same as the format originally fitted at C38 in p/n: 250407 boards. (Later boards had a additional pad allowing easier fitting of radial type caps as well as the pads for axial types).It doesn't really matter which type you fit, both are offered in case aesthetics are important.
More info here

Restore key mod capacitor -radial disc type 4.7nf

Restore key mod capacitor for Breadbin C64 - radial disc type

It has been found that replacing C38 with a 4.7nf capacitor improves the response of the restore key, ie: when modded, pressing RunStop+Restore should respond with the same pressure as any other key.
This is an radial type capacitor (both wires emerge from same end of cap). This type of cap was often fitted at C38 in p/n: 250425 boards though these could take axials too. It doesn't really matter which you fit, both are offered here in case aesthetics are important.
More info here

Small sachet of thermal grease

Suitable for renewing old, dried up thermal grease found on some versions of the C64
Note: This is thermally conductive grease, not adhesive.

3 Metres of flux-cored 60/40 tin-lead solder

Good quality, 0.7mm diameter - ideal for fine electronics work.

TOLB Module from Eslapion - NTSC Version

A replacement for the MOS 8701 clock generator chip used on boards 250425, 250466, 250469 and the C128. Works on the C64 Reloaded too!

Onboard oscillator makes it independent from the C64 crystal and easy to convert a C64 from PAL to NTSC and inversely
Consumes only 9mA of power (a genuine MOS 8701 consumes 25-30mA)

Compatible with Commodore computers (with the PCB numbers stated above) carrying these video chips:

MOS 6567 – Original NMOS version used in most C64 sold in Japan and North America
MOS 8562 – HMOS-II version used in most C64c
MOS 8564 – VIC-II E C128 version

300+ units sold - not a single defect and not a single compatibility problem found.

PCB colour may vary - current stock are green.

TOLB Module from Eslapion - PAL Version

As above but PAL version. Compatible with Commodore computers (with the PCB numbers stated above) carrying these video chips:

MOS 6569 - Original NMOS PAL VIC-II (breadbin C64s)
MOS 8565 - HMOS PAL-VIC-II (most C64Cs)
MOS 8566 - VIC-II E PAL (C128)

PCB colour may vary - current stock are green.