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Ti 99 4a with a ti 99 4 power pack and internal board help


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This is my TI-99/4 power unit that came in my 1980 TI-99/4A. Orange wire should be +5v..but i get -6.71 vdc, black wire should be +12v..but get -11.99. And green wire should be -5v and i get -17v.

 

So i would think it fried my motherboard.

 

What could have went on this to cause such voltages? And yes :) i have right wires on my fluke going to white wire common. :P

 

I think the fault is this brown cap but dont know what it is..any ideas?

 

If i can get motherboard working..i have an idea for a replacment wall wart and power board replacnent with a very available and common wall wart. (details on this to follow).

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