Freed Transformer numbers

[Walter66]

Hello,
old Freed audio signal transformers often had just printed Numbers instead of other designations on the transformers.
Unfortunately, they had no data other than that number stamped on it. No pin designations, no values of coils, no impedances.

Is there any known source where those numbers and their connections to technical data is listed on the web?
Those numbers may be military speced and could be alternative designations for real catalog numbers. But even Freed transformer catalogs are hard to find now on open sources.
http://www.bunkerofdoom.com/xfm/

I contacted this company, which seem to be the successor to Freed transformers, but no answer from them to my request.
http://electronictransformercorp.com/

Maybe someone can give a hint where to start searching? Thank you.

 

[TimG]

You could go to some of the big surplus electronics houses and manually scrape their data for the transformers they list?

SurplusSales dot com

 

[TimG]

Here is a 1969 catalog from Archive.org
What era do you need?

 

[Walter66]

Thank you! The era is post- war transformers, maybe up to 1960's. They have five digit numbers stamped on it. No catalog numbers from "The MASTER" will match them, Surplus sales don't list those types either.

 

[TimG]

There is a 1230 model in the 1962 catalog of a Decade Inductor.

 

[CJ]

You building the Lange solid state equalizer?

 

[Walter66]

Nope. Electron tube projects only.

 

[map2112]

Here are two Freed catalogs

 

[map2112]

For unmarked Freed transformers, including Mil versions which are generally not marked with a model number, I generally start by taking the measurements of the case and look it up in the catalog to help narrow down to a series and then take some DCR measurements to further narrow down possible candidates. From there you can follow all of the techniques to determine winding ratios and such.

A few of the Freed audio transformers feature multiple taps such as the U-500 designation (50, 125, 200ct, 250, 330 and 500ct).

I havent found any drawings showing the actual pin out for the connections, but have used the UTC catalog to figure out possible wiring connections, and make a cross reference of the pin numbers to the Freed terminal numbers.

Mark