Audio transformer two extra wires ??? - Printable Version
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+--- Thread: Audio transformer two extra wires ??? (/showthread.php?tid=22027)
Audio transformer two extra wires ??? - radio1 - 01-11-2021
Found this in Model 70 last audio transformer.
The top coil had large glob of wax on one side of the top input coil and when I melted it off with dryer I found these two white extra wires coming out from the inner side of the top coil. The top coil's inner and outer go the terminals as I suspected, and the lower coil goes to one terminal and the the other to ground as it should.
Anyone have a clue? Should the be connected? They do not show on the schematic.
The ends of the these mystery wires seem to be stripped at the ends. Was this just a mishap on winding?
RE: Audio transformer two extra wires ??? - morzh - 01-11-2021
Why do you call it Audio transformer? It is not.
I wonder if it is the replacement of LC filter after the audio detector, they just used it as an inductance?
RE: Audio transformer two extra wires ??? - radio1 - 01-11-2021
My bad, Its the coil before the second detector 24 (second IF transformer- part 03092). I have no clue yet, the white wires were under the glob of wax, and when I pulled them out that's what I see. They are very, very fine cotton covered. I wonder if this the correct coil or not. The top coil measures 7.0 mh and the bottom measures 4.0 mh.
RE: Audio transformer two extra wires ??? - morzh - 01-11-2021
I think I was right, this is the audio detector (2nd detector) choke. It probably opened and was replaced by a coild taht was lying there nearby.
Here is the link to my Philco 90 where the recommended value is 2.5mH. They use the same exact choke in both radios with the plate detector.
https://philcoradio.com/phorum/showthread.php?tid=8106
RE: Audio transformer two extra wires ??? - radio1 - 01-13-2021
Good thread, thanks, my plate RF choke measures 10mh. The one in the pics that I am referring to is the second IF transformer that feeds the final audio detector. Still don't know what these are or why. Strange enough, found an eyebrow hair preserved in the wax.
RE: Audio transformer two extra wires ??? - morzh - 01-13-2021
Send it for the DNA test
