Any idea where these mod trannys were used?

[N0BST]

Got a couple of mod trannies, one made by Stanley Transformer and the other by Freed, but they're identical- primary 8K-CT @250mA DC bal., 1690 WV; secondary 2.8K 300MA 1750WV, and a feedback winding  285 ohm CT, 1mA DC bal., 250WV 0.04W.  It's rated 200-20K CPS.  They look military grade and since there are a bunch of you who run old mil stuff perhaps you could tell me.  I was looking through some tube data sheets and nothing jumped out at me as to what bottles might have been used with these.  I'm also trying to figure out whether to hang onto or sell them.

Also have a 1H choke, 700mA @ 1600WV and a 16.7H choke 90mA @ 285WV that look fairly similar to these.

Thanks in advance,

Scott Todd

[KE6DF]

I believe they were used in some Vietnam era UHF equipment - a 4x150 modulated by 811s or 4-65s.

Here is a thread about these from this site:

http://amfone.net/Amforum/index.php?topic=29945.0

If they are the ones I'm thinking of they are kind of tall and not too wide.

Perhaps a picture???

I think it was from the MD-129 or MD-141 modulator.

[KM1H]

The Navy was using the 4X150A and PP 811's from well back in the 50's to well past the 60's as the standard 200-400mc shipboard TX. Cant remember the model as they almost never required service.  Made by CBS I think.

Carl

[N0BST]

If they are the ones I'm thinking of they are kind of tall and not too wide.

Perhaps a picture???

A very apt description.  Now to get a schematic of one of those units and scale the RF components to the HF bands and it sounds like it would be a pretty good rig.  Too bad the 4X150 doesn't have the pizazz of a 4-125.

Scott

[KE6DF]

Look on the bunkerofdoom. The schematic is there.

[WD8BIL]

The Navy was using the 4X150A and PP 811's from well back in the 50's to well past the 60's as the standard 200-400mc shipboard TX.

Was that the ol' TED/RED series, Carl?

[N0BST]

Look on the bunkerofdoom. The schematic is there.

Yep- made plenty of notes.  This should be fairly easy to do, assuming I can find the rest of the iron, especially the bias and HV trannies and chokes.  Too bad the FCC doesn't allow domestic SW broadcasting.  This thing would loaf along for years of continuous use.

Scott

[KC4VWU]

 Too bad the 4X150 doesn't have the pizazz of a 4-125.



Scott
[/quote]

Say whaaaa? Have you compared the specs?

---Phil

[KM1H]

Was that the ol' TED/RED series, Carl?

It was after that with a URT something designation. Paired with a URR-35. Looks similar to the TED and URR-7 but UHF.