Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

511 series AF transformers
#1

After replacing a burned out 71A tube I was getting one strong channel but no volume control. I figured I'd recap it and see what I got. While waiting for the new caps to arrive I went through the chassis more thoroughly and found that the output choke was taken out of the circuit with the speaker connected directly to the 71A and worse, the 2 AF transformers (#3077) appear to be open... I doubt I'll be able to find replacements and I don't want to put a lot of money into it. Is it possible to rewind these myself or use some modern replacements?
#2

Hi

While these can be rewound, modern replacements are available for the audio interstage transformers from a few sources. You will want transformers with a 1:3 ratio.

Or, you could change the audio interstage transformers to resistance coupling. Details here:
http://www.philcoradio.com/tech/audio.htm
Scroll down to "Modification C."

--
Ron Ramirez
Ferdinand IN
#3

Thanks Ron, I will try the resistance coupling if I can't find an appropriate match. This may be a silly question but, could I use a 110v to 36v power transformer (1:3 ratio) as a substitute? Also what kind of current rating should be used?




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Hickok AC51 tube tester
Note that no power cord, power switch, or power transformer switch are shown. That (along with my experience with full s...DaleHCook — 07:09 AM
IF can wire size and Rubber mounts?
A pair of wire strippers can give you an idea of what the existing gauge of the wire leads are in the IF can, I think it...Arran — 06:07 AM
My last cabinet for this year
Hello Dan, That is really beautiful what great looking radio you have ! I have friends who live in Calgary and the wea...radiorich — 01:51 AM
12' Philco
Not anymore Mike. Andre The Giant Born: May 19, 1946, Coulommiers, France Died: Jan 28, 1993 (46 years), Paris, Fran...RodB — 11:53 PM
IF can wire size and Rubber mounts?
Renovated Radios do carry what you need. As for the voltage, a wire should be at least 300V-rated.morzh — 11:13 PM
12' Philco
Andre the Giant got 2" on Kareem :lol:morzh — 11:11 PM
IF can wire size and Rubber mounts?
Thanks for the info but I doubt that a hardware store would be carrying the proper tuner assembly support mountings for ...georgetownjohn — 10:38 PM
12' Philco
Perhaps Kareem Abdul Jabbar?GarySP — 10:33 PM
My last cabinet for this year
Outstanding work, Dan! Take care and BE HEALTHY! GaryGarySP — 10:31 PM
My last cabinet for this year
They are a nice looking radio, Stromberg. I have a small tabletop octagon-dial one. It sounds surprisingly nice. And t...morzh — 09:40 PM

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

>