Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12, 2025) x

Thread Closed

Philco 20 volume control problem
#2

I just had this radio out and cleaned the control. It played on the bench for three hours, no problems. I reinstalled it in the cabinet and continued to play it. While the volume control is working normally, I have noticed that randomly the volume will drop slightly. If you leave the radio alone it will suddenly come back up. If you raise the volume with the control, when it drops, when it comes back it is way too loud for comfort. I have monitored the output tube bias on the 71's and that stays constant so it isn't a problem with the transformer. I am not able to get to the 27, first audio to monitor any voltages. I have substituted all of the 24's and the 27 with known good tubes and that isn't helping. Thanks guys.


Messages In This Thread
Philco 20 volume control problem - by Tubesforme - 02-01-2017, 06:13 PM
RE: Philco 20 volume control problem - by Tubesforme - 02-01-2017, 06:55 PM
RE: Philco 20 volume control problem - by KCMike - 02-01-2017, 08:12 PM
RE: Philco 20 volume control problem - by GarySP - 02-03-2017, 12:17 PM
RE: Philco 20 volume control problem - by morzh - 02-03-2017, 11:05 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
under chassis parts locator diagram for 1938 Zenith 9s262
Has anyone gone to the trouble of creating an under chassis parts locator image?  Yes, I can identify components by foll...bobloney — 08:57 PM
Plug Voltages Needed For A 1943 CRV-20130 Power Supply
Try looking at this site the book mark is for a old generator that I was given. David    https://radionerds.com/index.ph...David — 08:36 PM
Plug Voltages Needed For A 1943 CRV-20130 Power Supply
Hello Everyone, I am looking for voltage identification for all the pin positions on the socket of a CRV-20130 power su...Tonym4704 — 08:16 PM
Philco P45-6365 Universal Transformer Instruction Manual
Can anyone guide me to where this may be found?GRG — 03:00 PM
54C Complete Teardown/Rebuild
I don't think that I have encountered a 12Z3 before, curious how it uses one of those but includes a #43, which is a 25 ...Arran — 02:17 PM
HiFi (Chifi) tube amp build - but my own design.
It's the other forum. I'm also in DIY, but mostly read there. Honestly, I kinda jumped into this without much thought to...TV MAN — 10:43 AM
Philco 71 Code 125
Hello,  I am in need of a schematic for this radio. Mine has the three separate circular tube shields and a shadow me...dconant — 08:06 AM
Stromberg Carlson 1500 Squeal
And life just keeps getting more complicated.dconant — 07:57 AM
54C Complete Teardown/Rebuild
Hello Roy, here is this one sincerely Richardradiorich — 12:45 AM
54C Complete Teardown/Rebuild
Richard, Had grabbed it already but thank you just the same.  I find myself wanting to find some way to block out the...glyphmon — 12:03 AM

[-]
Who's Online
There are currently 1909 online users. [Complete List]
» 2 Member(s) | 1907 Guest(s)
AvatarAvatar

>