• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Transformer/Choke? with 3 wires.. from old TV

Hi, I have a collection of these transformer/choke looking things that i’ve salvaged from various TVs over the years. I’m wondering what they are.

They have 3-wires, and when i search “3-wire transformer” I don’t get any relevant results on google.

Are they chokes, autotransformers, or something else? they seem to measure quite high in terms of DCR (1.2k ohms) and inductance (40H) with the center tap being quite close to one of the ends.

I’ve tried to look for old TV schematics to see if i can spot something that might be them, but i’m either not finding the right schematics or I’m not looking for the right symbols.

Please help!

CCE46616-72E4-4ABA-8ECB-04B7FCDB1C09.jpeg
 
Yes, they are likely vertical sweep OPT's. Some early low cost TV's used a 3 wire autotransformer to drive the deflection yoke at 50 or 60 Hz depending on where you live. The 4 wire versions do make decent OPT's for low power SE amps. In my youth I simply lifted the entire vertical section from a TV, disconnected the feedback cap and put a guitar jack in it's place. That was in the early 60's and the TV's were scrap, so they were from the 50's. The early Bottlehead SEX amp did the same thing but used a different jack for a HiFi amp.

These should not be used for a HiFi amp as it will put B+ on your speaker leads.
 
  • Like
Reactions: efm7