All -
I am looking for an output transformer for my Philco 39-6 and am hoping that someone has a junker chassis / speaker which they could sell me the transformer off of. The radio is question belonged to my great grandparents and has quite a bit of sentimental value and so I am trying to keep it as original as possible, hence my request here for an original part as opposed to hacking in a modern universal replacement. I don't have a part number for the transformer, but will do my best to describe its critical features. It is mounted on the back of the speaker in the same manner as most all Philco table radios from the era. However, its input impedance is much higher then that used for later sets - I estimate the impedance of the primary of the transformer to be in the range of 8,000 - 10,000 Ohms. The primary resistance is 850 Ohms, per the Ryder's schematic. Any leads will be appreciated!

Thanks in advance,
Matthew D'Asaro

Is a winding open? If so, it may be repairable with a little cautious digging to see if it is broken where the winding ends are broken out (pig-tailed?) to connect to the terminals. Or, you may try Playthings of the Past or other parts vendors.
Good luck!

Thanks! I already tried fixing it. No luck. The break is somewhere in the middle of the thousand-plus turn secondary.

-Matthew

Yeah, after I posted I looked at who the OP was.
Well, best of luck.

HELLO
send me a pm i may have what your looking for ,long shot but worth a try
thanks
bob

just a shot in the dark you may see one

Thanks Bob, but none of those look right. Sorry.

-Matthew

One idea:
Take off the covers on yours and measure the core dimensions**. You may be able to find an output trans that is the same, and then just put your covers on it.

**There is a standard geometry in which the core is made with no waste. If you have this, it should be relatively easy to find a transformer that will fit.
Here is the layout of the "scrapless" configuration: (The non-standard variable is the thickness)

The transformer has no covers. It is just the outside paper on the coil that shows. I took the core out to try and rewind - that is until I realized that there were over 1000 turns and was hoping that I could find something modern that would fit. However, I could find very few modern output transformers with such a high primary impedance that were small like mine. I will post core dimensions and hopefully someone has an idea.

-Matthew

Still looking...

-Matthew

http://item.mobileweb.ebay.com/viewitem?itemId=300720168906

It looks rough outside.
I suspect that Rick of the "American Repainters" tv show may have gotten to it.

Thanks. I looked through Hammond's catalog, but all of their single-ended transformers are physically too large but model 125B, made for push-pull circuits, looks like it will fit. It also looks like it can be configured for the correct primary and secondary impedances. Will a push-pull transformer work in a single-ended application like this?

-Matthew