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Old November 13th 06, 03:04 AM posted to rec.antiques.radio+phono,rec.radio.amateur.boatanchors
Chuck Harris Chuck Harris is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 270
Default Looking for 50 KHz IF used in Hallicrafters....

Steve wrote:
Chuck,
Already tried to repair it. The break is in the coil, not
at the terminals, or exposed wires.


RATS!

The coil is encapulated
in a ceramic goop I've never seen before. Removing it
will destroy the windings. As a result it'll be hard to count the
windings (its a center tapped coil with unknown tap)even
if I have to rewind it.


I've seen this stuff before. It shatters pretty well on
coils. You might be able to get it off of the coil and
count the turns... but they you are bound to find that
the coil is wound in litz wire.

Also tried the high voltage arc technique where you use
a HV supply with a big (12K ohm, 10 watt) resistor
in series hoping to weld the break to another adjacent
winding. This worked briefly...


I have had good luck doing this with a Sencore Z-Meter capacitor
tester. I keep upping the voltage until I get continuity. Then
I blast it a few more times for good measure.

-Chuck



Groan.

Steve
"Chuck Harris" wrote in message
...
Steve wrote:
Just discovered that one of the IF cans in my SX-117 has an
open winding. I know that many Halli receivers used the
50.KHz IF, and probably the same coil. The part number
is 050-200735 which is printed on the top of the can.
Thanks!

Steve

Why don't you fix it? It's big, and the failure is almost always
right where the wire is soldered to the terminal.

-Chuck