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

Question about replacement transformer for 37-660
#1

I have am looking for a replacement for the output transformer for this radio. I have a line matching transformer with 5 primaries: 500 ohm,1k,2k,4k,and 8k. Output is 4ohm or 8ohm, listed as 10 watts.
Radio schematic calls for 370 ohm and 330 ohm ct primary on transformer (has two 6f6's)
Will this work on this radio? If not, any suggestions on what will work for a replacement?
Thanks,
Bill
#2

Just remember that those "300 ohm" DC resistance numbers on schematics have nothing to do with audio impedance values. You can forget those DC numbers for this exercise.

You should be up in the 'several K' numbers for impedance on the primary. I'd go with the 4k/8k options. It will vary if you feed a 4 vs an 8 ohm speaker. An original Philco speaker of that era will be closer to 4 rather than 8 ohms. I think they lean towards the ~ 2.6 ohms neighbourhood .

The AF xfmr behaves as a 'ratio' animal to match the tubes to the speaker at AUDIO frequencies. Just try it and see. Dunno your specific transformer but you should be able to come close to spec. Lots of leeway.

-Bill
#3

Thank you for your help. I will try it at 4k.8k primary, l don't understand the impedance vs resistance on these transformers. It does have an original philco speaker, but not from this radio. Is the 330/370 ohm value in the schematic significant as far as the load on the audio tubes?
Thanks,
Bill
#4

Hi,
No, those resistances are simply noted as a troubleshooting aid so that a repairman would know what to anticipate while troubleshooting with an ohmmeter.




Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
Hi Cap'n Clock, Unfortunately, I do not have this radio.  This is a shame because this should be a good performer.  2A5...MrFixr55 — 06:48 AM
American Bosch Model 802 auto radio
I think it would come under either American Bosch or United American Bosch. American Bosch made sets for the American We...Arran — 05:53 AM
trying to identify this wire type
Thanks to all for the feedback. As Arran said, it is probably an older replacement and yes it has a grid cap so I will ...georgetownjohn — 09:32 PM
trying to identify this wire type
It's possible that the red wire, actually a grid cap lead, is a very old replacement, I can't remember seeing a pre 1939...Arran — 09:18 PM
Gilfillan Brothers Car Radio?
Hi everyone,  Special thanks to Joe Rossi for tracking down this obscure radio and thanks to others who took up the hun...Antipodal — 08:15 PM
trying to identify this wire type
Here's one source for your wire of many. Take care and BE HEALTHY! Gary P.S. Can't get the right color you need? I ...GarySP — 06:40 PM
trying to identify this wire type
...and modern wire of the appropriate gauges and insulation V-rating (300V minimum, usually shown right on the wire) is ...morzh — 05:47 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
I have a question about this radio, is there anyone that has access to this radio that has an intact unmolested speaker ...captainclock1988 — 04:28 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
Well what makes me confuse all of those companies is that all three of those companies (Setchell-Carlson, Stromberg-Carl...captainclock1988 — 04:21 PM
trying to identify this wire type
The red wire is rubber covered wire. The others are cotton braid over rubber often in colors or a tracer, also strand...Chas — 02:43 PM

[-]
Who's Online
There are currently 5555 online users. [Complete List]
» 1 Member(s) | 5554 Guest(s)
Avatar

>