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38-93 low volume
#9

Agree with John on this....
Follow the B+ from the FC to the plate of the 6F6. You have to check the FC for resistance as well as the primary of the OPT. These are static tests. The OPT should measure 400 ohms +/- 10%. The FC 1140 ohms +/- 10%. Another check would to make sure the 6F6 isn't shorting. These tubes run HOT to begin with but a short will drag down the voltage considerably. If you can, recheck the status of your e-caps. More than once I've installed new e-caps that weren't up to par and leaky.
Is the transformer getting too hot? A good way to spot this trouble is to monitor the AC primary with a 0-2 A ammeter. Down and dirty, divide the name plate wattage by the incoming AC voltage and it'll put you in the ballpark on how much amperage you're supposed to be drawing.

Good luck with the project and all of us here are expecting a full report when you're finished.


Messages In This Thread
38-93 low volume - by NostalgiaRadioTime - 04-03-2017, 09:51 PM
RE: 38-93 low volume - by Radioroslyn - 04-03-2017, 10:41 PM
RE: 38-93 low volume - by NostalgiaRadioTime - 04-03-2017, 10:52 PM
RE: 38-93 low volume - by NostalgiaRadioTime - 04-03-2017, 11:03 PM
RE: 38-93 low volume - by morzh - 04-03-2017, 11:08 PM
RE: 38-93 low volume - by Arran - 04-04-2017, 04:03 AM
RE: 38-93 low volume - by John Bartley - 04-04-2017, 07:38 AM
RE: 38-93 low volume - by Mondial - 04-04-2017, 09:15 AM
RE: 38-93 low volume - by Jim Koehler - 04-04-2017, 09:21 AM
RE: 38-93 low volume - by NostalgiaRadioTime - 04-04-2017, 10:08 PM



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