Re: Dead PET 2001

Re: Dead PET 2001

Date: Tue, 28 Jul 2009 19:12:38 +0200
Message-ID: <>
Hallo Philip,

> I have measured the voltages on the motherboard...

More important is the voltage at the input of the 7805 voltage regulators. 
IIRC that should be about 9 Volts. 
If that is near zero as well, it could be there is a shortage, or the 
transformer is dead.

Check the top right of schematic
Disconnect the power connector and check the AC voltage between pin 1 & 4 
and 5 & 4. IIRC should be about 12 volts AC.
Now you can check the diodes.
If all is OK so far, desolder the inputs of the 7805's and connect a 21 
Watt 12V lightbulb. Should burn without any problem. 
If no problem so far, connect the pins of the 7805's one by one. 

Keep us informed.

   / __|__
  / /  |_/     Groetjes, Ruud Baltissen
  \ \__|_\

       Message was sent through the cbm-hackers mailing list
Received on 2009-07-28 19:21:37

Archive generated by hypermail 2.2.0.