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

Bad Output Transformer
#1

Well I hit a snag on my 42-1008 project:

the output transformer (#73 part no. 32-8133) primary is reading 4.7Kohms on one leg to the center tap and 180 ohms from the other leg to center tap. The secondary is .6 ohms.

Does anyone have any suggestions on what to do about a replacement or substitute?
#2

John Kendall at http://www.vintage-electronics.com/rjy.htm
has a 42-1008 chassis for parts. You would need to email him to see if he has the output transformer available. If not you could go the universal Hammond transformer route. Radio Daze sells these.
#3

Failed output transformers seem to be a common problem with early 40s Philcos, but the usual failure is an open primary not shorted turns. Have you disconnected anything tha may be connected in parallel to the primary? If it does turn out to be defective I would try to find a push pull output transformer from a parts set that is NOT an early 40s Philco or a new one, or an aftermarket NOS replacement. Harvesting one from another Philco chassis of the early 40s may be a wasted effort, you may end up with another dud that way.
Regards
Arran
#4

The schematic shows the primary should be 220 ohms from center tap to one leg and 200 ohms from center tap to the other leg. It also says the secondary should be .2 ohms.
#5

Does anyone know what I'm looking for in a replacement transformer? I have no idea what power rating, impedance, etc. that is needed for this application.
#6

32-8133 specs:

Primary impedance 17,000 ohms center-tapped; secondary 5 ohms; 6 watts; turns ratio 58:1.

A Hammond 125C would be a good replacement. It looks like you would want to connect your speaker voice coil across either output terminals 1 and 3, or terminals 2 and 4 (whichever one gives greatest volume).

--
Ron Ramirez
Ferdinand IN
#7

Thanks for the info, Ron. I really appreciate it. Icon_smile




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
HiFi (Chifi) tube amp build - but my own design.
Tim, nice write up and thanks for sharing !! Sincerely Richardradiorich — 02:47 AM
HiFi (Chifi) tube amp build - but my own design.
Well, this was a real "Hum-Dinger" :lol: ! This will be kinda long, but hopefully it will help others having t...TV MAN — 01:55 AM
Shadow Meter Bulb
Phorum members, I am trying to find the bulb # for PHILCO Shadow Meter part number 45-2180 that is from a 37-640 chassis...georgetownjohn — 06:53 PM
Philco 41-608 changer coupler
3D-printing...short of machining, of course. Or molding.morzh — 05:20 PM
Philco 41-608 changer coupler
Thanks, Morzh. That solves the issue of the rubber pieces. Now, I need to find a way to replicate the pot metal piec...alangard — 05:07 PM
12' Philco
If it is 12', either Kareem or Andre would have to jump pretty high to look at the front panel. Kareem would have an e...morzh — 01:48 PM
12' Philco
And here's a story about the tires on the truck. Same "no-stoop" guy must have installed these! Take care a...GarySP — 01:17 PM
Hickok AC51 tube tester
I think they have only shown the secondaries of the transformer. Two of them feed the rectifiers' filaments.morzh — 12:58 PM
IF can wire size and Rubber mounts?
Arran If the wire inside cans is the gauges you mentioned, the sole reason for that would be mechanical, to stiffen t...morzh — 12:56 PM
12' Philco
Rod, Yes, I know, but the Giant Philco is not around anymore either, so I go by whoever was alive fairly recently. H...morzh — 12:54 PM

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

>