G9, No 15 v output voltage. Any Ideas??

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StrayCat

Well-known member
Joined
Jun 7, 2004
Messages
83
Location
Nova Scotia
Hi, and a feeble cry for help. I have just assembled my first G9 and cannot get voltage out from the 15vac output on the PCB. Looks like there is not very much between the 15VAC/1A input and the 15V out put to the step up transformer.

Tubes are heating up and so is IC2. My PCB is only grounded at the 245v header, used for the off board caps. could this be it?

IC2(78S12) has voltage but it keeps on fluctuating from the 20's VAC to high 40's VAC.

All the diodes checked out from 15VAC/1A in to 15 VAC out.

Any suggestions? If anyone has any test points for checking voltages it would be greatly appreciated.

Thanks for any and all info on this.
 
Hi!

Please can you calrify or post some pictures.

Something sounds wrong. There should be no 15V AC output from the PCB. There should be 15V FROM the transformer TO the PCB, plus a high voltage (220V ?) from the step up (second) transformer TO the PCB.

Look at the schematic very carefully again.

Cheers!
Stewart
 
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