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Nothing but slight hum from 37-620
#4

I've checked both IF transformers with an ohm meter and they seem fine.

Connecting the antenna (both by way of a random long piece of wire and by way of a jumper from the grid cap wire from the 6k7) to the 6a8 doesn't result in any change. But i'm not sure what should happen?

In terms of voltages:

I'm not entirely sure how to go about checking them. Going from chassis ground to the points labeled in the "socket voltage" section of the rider results in the following for the 6a8:

"P": 265ish ... should be 245
"S": 63ish ... should be 70
"OSC R": 120ish ... should be 150

and for the 6k7:
"S": 62ish ... should be 70
"can't read it": 265ish ... should be 245

the filament voltages for both are normal.

I do have a signal generator if that would help. It is a modern new fangled digital thing (telulex sg-100/a). I'm not sure if it is useful in this case.


Messages In This Thread
Nothing but slight hum from 37-620 - by audin - 01-08-2011, 09:20 PM
Re: Nothing but slight hum from 37-620 - by audin - 01-09-2011, 12:30 AM
Re: Nothing but slight hum from 37-620 - by audin - 01-09-2011, 09:21 PM



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