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What to do ....
#1

I've got this model 84B that has an open secondary on the IF transformer. It belongs to a fellow Phourm member. He sent me a pm and asked if I could take a look at it for him. I agreed started to work on it. He did a great job replacing all the caps and resistors so all I really had to do was figure why it wouldn't play. Well the oscillator wasn't running so out came the coil rewound the feedback winding. But that didn't fix the oscillator so after some troubleshooting I found the secondary on the IF coil was open. With that open I guess that changes the load on the mixer tube and stops it from oscillating.
Now I'm faced with another problem how to fix this thing without a IF transformer. Haven't been able to find a replacement. Was thinking I might just use a standard replacement retune it to 450kc and use a 1N34 for the detector. So was wondering if there are any other ways of fixing this problem? I don't know if the owner wants to spend the cost of a whole other set to fix up this thing.
Tnx
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!

Terry
#2

Many times the "open" is a corroded base terrminal where the primary and secondary windings connect to the lugs.
Philco is notorious for this condition.

Also, if the "open" is only a few windings into the coil, un-winding the wire until you come to the break ans re-soldering the "good" end to the lug should get you by without a replacement or total rewinding. The few turns off one winding will not effect alignement enough to notice.

Obviously, if the break is more than a few turns into the coil, then you should replace or re-wind.

Chuck
#3

Well Chuck
This time I took your sage advise and popped the IF coils out and after digging around I found the bad connection. She's up and running the Phills are tied 2-2 in the 9th.
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!

Terry
#4

Glad to help. It takes a little extra work to open up the cans, but many times that's the culprit.

Chuck




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