Dk Tronics 64k proble

[simondo]

Just aquired a dk Tronics 64k but it is not working identified as such by not by no speech in Robocop and other 128k games not loading. Connectors cleaned but still no joy. My other dk 64k works fine.


This is a through hole PCB model. Is there any way to investigate & fix problem?

[Bryce]

Probably dead RAM. They need to be diagnosed and replaced just like an internal RAM problem.

Bryce.

[simondo]

Thanks Bryce.

I have some 256k ICs lying around so I will do this mod: http://www.cpcwiki.eu/index.php/Upgrading_a_Dk%27tronics_RAM_Expansion

Mine is a version with socketed RAM ICs but has 74LS74 and 74LS153 ICs already fitted in the top left positions, photo attached.

Will replacing 64k RAM with the 256k and cutting the 2 jumper tracks and joiniing horizontally work on this model?

Admin, please use this photo to add to DK Tronics Expansion gallery for reference.

[Bryce]

Yeah, it should work fine. If it still doesn't work with the 256K RAMs, it's time to find out what's really broken though.
Have you checked all the solder joints to the edge connector? They might have cracks.

Bryce.

[simondo]

Got it working now. Took casing off and cleaned male edge connector with glass fibre pencil & IPA👍.


I'll try the 256k ICs next.


Many thanks Bryce.