Re: Non-working Commodore PET 3016
The voltages seem to take a minute or so to stabilise after powering on - does that make sense?
VR6 pins top to bottom:
+0.02v
-12.40v
-4.97v
I am using the earth screw as the earth point - I have also tested using the right end of the large capacitor and got the same answers.
The VR6 is marked LM7905CT
With regard to the PET, I bought it as a known non-worker for £50 off ebay in 2012. The case is rusty and will need attention which I'm comfortable with. It came from a shed in a garden in Dumfries.
Current fault symptoms - nothing on the screen so I find it tricky to give any more detail than that. I have three external cassette drives for when I make some progress - some of my original cassettes are also in the attachments fyi.
I attach some photos of its current state and some photos of the 2012 state.
In 2012, I cleaned the motherboard with 99% IPA to get things a little clearer.
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