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89 oscillator check
#1

I removed the oscillator coil and baked at 200 degrees for 30 min. I cannot see any breaks in the winding but I'd like to test it further. Is there some sort of Ohms test I could do between the five soldering lugs and the wire to the top of the tube? Where should I get readings and what? thanks.
#2

O.K. if I'm reading this right I should get 5.2 Ohms between the lugs for the small outer winding. The first two clockwise from the clamp and connecting between the 77 tube and a cap and resistor. Right? I get nothing. Any pointers on how to rewind and what to use? Thanks again.
#3

Chuck has coil winding info on has site, but no specifics for the model 89:
http://www.philcorepairbench.com/tips/svctip36.htm

Carl
Northern Panhandle, WV
#4

The winding in question connects from pin 5 of the#77 tube (cathode) to the cap and resistor in parallel. Should measure on the order of a few ohms. Bad ones will measure a few 1000 ohms. For winding details see the Philco Model 80 post.
Terry

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got it!

Terry
#5

Yeah but what gage wire do I use on an 89 primary coil?
#6

If you mean the feedback winding (cathode) anything from 30 to 36g is fine. It's not very critical as it doesn't determine the frequency. It just determines whether it oscillates or not.
Terry

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got it!

Terry
#7

Thank you!
#8

I use 38 gauge as that is what was used originally. Most have 28 turns although I have found some that have 24 turns.

Wind the winding clockwise, as you are looking at the bottom of the coil where the terminals are.

--
Ron Ramirez
Ferdinand IN




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