Time for a downgrade...

So those that have been reading this blog for a little while (yes I know who all 3 of you are) might remember that I bought a Commodore 128 back in 2014.  What I don't think I mentioned at the time, was not only did I never previously own a Commodore 128 - I had never actually even touched one in the flesh.

It's been a fun machine to play with - but it doesn't have that same nostalgia that the Commodore 64 has for me personally.  So this week I sold my Commodore 128 and bought a non-working Commodore 64 (working ones go for ALOT more).


So before plugging it in I opened it up (Dave Jones style) just to have a look.



Inside does not look like it's had anyone in there in a long time.  No repairs or swaps that I can see.  Bottom of the board has some bubbling of the silk screen - seems quite common for these boards.


I got out my ESR and checked the caps - they are all within range but I've ordered replacements anyways given I only need 6 of them.


Once all that was done I plugged in my Ray Carlsen power supply that I bought for the c128 (I sold it without the supply), my Hercules Workshop video cable that gives me S-Video out and hoped for the best.  As the ad said when I bought it - nothing.  Just a black screen.  For those that don't remember, the black screen on a c64 is akin to the Red Ring of Death on an Xbox.

Consensus is that this is most often caused by a faulty PLA chip (these run quite hot normally and are not heatsinked so have a high failure rate).  I've ordered a replacement that will take a while to get here (so I didn't pay more than what I did for the C64 itself).

I've also ordered a set of sockets - as you'll notice most of the ICs are not socketed.  Any I replace I will socket when I do so.  I've also ordered a set of heatsinks.  I checked the 5 and 12 volt rails on the board and they are both fine.  None of the other chips got hot (I didn't leave it running forever).  Most people say that if a memory chip gets hot its probably shorted.

I have a diagnostic cart - but that doesn't work either.  Same black screen when I use it.

So I'll wait patiently for a couple of weeks for the bits to turn up that will hopefully (with a bit of luck) bring this guy back to life!

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