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

Thread Closed

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



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
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
54C Complete Teardown/Rebuild
Hello roy, here is a link to the schematic . Sincerely Richardradiorich — 11:54 PM
54C Complete Teardown/Rebuild
Richard, The Silvertone 2014 also is a transformerless set, so I am incorporating a 1:1 600 ohm audio isolation transfo...glyphmon — 11:37 PM
Preliminary work on wife's Silvertone 2014
Did an alignment today which was interesting.  IF alignment went great, almost all was already spot-on.  Adjusting on th...glyphmon — 11:35 PM
54C Complete Teardown/Rebuild
The main problem with adding a Bluetooth input is that this set lacks a traditional power transformer to isolate it from...radiorich — 11:19 PM
54C Cabinet Refinish
I started stripping this cabinet before it got super chilly out because I knew I wasn't going to be able to work on ...glyphmon — 11:18 PM
54C Complete Teardown/Rebuild
While I'm waiting to wrap up the final steps on my wife's Silvertone 2014, I started disassembly on the next project.  O...glyphmon — 11:07 PM

[-]
Who's Online
There are currently no members online.

>