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38-116 input transformer
#1

Just started working on a 38-116 (code 125) console.   Chassis has been "worked on" before and about half the tube shields and bases have been cut off so that metal tubes could be used (ARGHHHH!).

Anyway, in looking over the underside of the chassis I found that the input transformer (number 102 on the schematic) has problems.  The two sections going from the grid of the 6L6 tubes are reading several kohms instead of the 150-175 ohms shown on the schematic.   I did make sure not to include the 10,000 ohm resistors nos. 100 and 101 in the readings.   Grid to grid of the 6L6s reads about 25K instead of slightly above 20K.  The two 10K resistors have been replaced and both read 10K so they are not the problem.

Also, the 400 ohm section from the  plate of the 6J5 driver reads about 750 ohms....

Any suggestions as to how to proceed?
   

Thanks,
Mark


Messages In This Thread
38-116 input transformer - by retiredinprescott - 11-11-2014, 06:41 PM
RE: 38-116 input transformer - by Mondial - 11-11-2014, 07:06 PM
RE: 38-116 input transformer - by Mondial - 11-11-2014, 08:03 PM
RE: 38-116 input transformer - by morzh - 11-12-2014, 03:56 PM
RE: 38-116 input transformer - by Mondial - 11-12-2014, 04:27 PM
RE: 38-116 input transformer - by Mondial - 11-12-2014, 04:50 PM
RE: 38-116 input transformer - by Mondial - 11-12-2014, 05:21 PM



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