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Philco Model 81 Help
#1

Hi All,

New member- first time poster.

I have a model 81 that I have rebuilt. Replaced all caps, resistors and rewound the ant coil (primary side).
The speaker cone is in bad shape but it plays.

The set is working and I can get a local station in my basement- so I am not too far from finished.  
I have been making voltage measurements on the tubes to confirm everything is in spec and I am having a problem reconciling the 42 output tube with the rider voltage chart for this radio.  Specifically, the control grid CG to cathode K. The rider manual calls for 2.3 V.  The 42 tube data sheet calls for a control grid voltage of -16.5 to -20 v. I am measuring about -17 v from CG to K (ground).  Not sure if I have a problem or not.

My plate, screen and filament voltages are in spec. (riders chart).

thanks for the help,

Anthony


Messages In This Thread
Philco Model 81 Help - by adiubald - 01-20-2016, 12:02 PM
RE: Philco Model 81 Help - by klondike98 - 01-20-2016, 03:16 PM
RE: Philco Model 81 Help - by Paul Philco322 - 01-20-2016, 08:18 PM
RE: Philco Model 81 Help - by morzh - 01-20-2016, 09:56 PM
RE: Philco Model 81 Help - by adiubald - 01-21-2016, 09:22 AM
RE: Philco Model 81 Help - by Arran - 01-21-2016, 04:02 AM
RE: Philco Model 81 Help - by adiubald - 01-21-2016, 09:29 AM
RE: Philco Model 81 Help - by morzh - 01-21-2016, 07:46 PM
RE: Philco Model 81 Help - by adiubald - 01-22-2016, 07:59 AM



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