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Stromberg 1-A transformer needed
1/7/2009 9:38:01 AMJim
Hi,
I need a transformer for my Stromberg-Carlson 1-A. The transformer is marked No. 3-A Audio Transformer. This couples two 201A tubes. The DC resistances are about 1000 & 8000 ohms (primary & secondary).

Has anyone had experience having these rewound? Any recommedations for rewinding services? Approximate costs?

Are there suitable substitutes?
Thanks, Jim

1/7/2009 11:09:14 AMDoug Criner
Substitutes are available from tubesandmore.com and radiodaze.com. These are 1:3 Stancor knock-offs. RadioDaze part no. HX-124A.

For $14.30, I don't think you want to try rewinding! But they also sell just the winding, that might fit on your existing xfmr core: $12.30.
Doug


:Hi,
:I need a transformer for my Stromberg-Carlson 1-A. The transformer is marked No. 3-A Audio Transformer. This couples two 201A tubes. The DC resistances are about 1000 & 8000 ohms (primary & secondary).
:
:Has anyone had experience having these rewound? Any recommedations for rewinding services? Approximate costs?
:
:Are there suitable substitutes?
:Thanks, Jim

1/7/2009 8:17:03 PMJim
Hi Doug,
Thanks. For some reason I overlooked those. I saw the Antique Electronic Supply transformer, but the 3:1 concerned me.
I appreciate the help, and will be buying one of those HX-124 (A or C) if an original doesn't come available.
Jim
1/8/2009 4:14:05 PMDoug Criner
If you are able to measure resistance on the primary and secondary windings, the existing audio xfmr is good.

The typical ratio for '01A audio interstage xfmrs is 1:3 (voltage step up), not 3:1. The ratio of DC resistances might throw you off if the two windings used different gauge wire.
Doug


:Hi Doug,
:Thanks. For some reason I overlooked those. I saw the Antique Electronic Supply transformer, but the 3:1 concerned me.
:I appreciate the help, and will be buying one of those HX-124 (A or C) if an original doesn't come available.
:Jim

1/8/2009 7:13:45 PMJim
Thanks Doug.
The radio has two of those transformers. Luckily, one was good, and that is how I got the measurements.

It is a great looking radio. I am hoping one of those you mentioned will fit inside the old housing so it can be kept original looking. I'll know soon enough (well, not really soon enough).

Your tip made my day.
Jim

1/9/2009 1:51:49 PMNorm Leal
Hi Jim

Your replacement transformer will have lower resistance. It's doesn't matter as impedance and turns ratio are what's important. The one Doug mentioned will work.

Norm

:Thanks Doug.
:The radio has two of those transformers. Luckily, one was good, and that is how I got the measurements.
:
:It is a great looking radio. I am hoping one of those you mentioned will fit inside the old housing so it can be kept original looking. I'll know soon enough (well, not really soon enough).
:
:Your tip made my day.
:Jim

1/10/2009 7:18:12 AMJim
Norm,
Thanks. I have much to learn!
Jim


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