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Ok started to look at this GE..
[Image: http://i292.photobucket.com/albums/mm38/...coeiav.jpg]
Looked nice on outside
[Image: http://i292.photobucket.com/albums/mm38/...o3jy4h.jpg]
Not so nice on inside..
As I was checking Transformer and coils I think I found a Coil open.. See schematic Its L1 I get no reading..
Question is do I really need that coil? Looks like it would work with out it.. Anyone have a Guess??
[Image: http://i292.photobucket.com/albums/mm38/...oyy42c.jpg]
Skip...
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You are lucky, it's a trap and you can forget it. Not needed.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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There is a capacitor in series with it so if you check it from the wrong test point it may read open when it isn't. However I can't see a reason why it would be open, and not the primary itself, since the primary is usually the one that gets knocked out first in a lightning strike.
Regards
Arran
(This post was last modified: 03-14-2017, 10:32 PM by Arran.)
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They simply rot out sometimes.
In any case this is a vestigial part and no longer needed so if the RF itself is good I'd not worry about it.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Thanks all.. Thats what I thought it was. But wanted to make sure.. L2 is fine.. And yes I was measuring before the Cap..Coil only...
The IF's and Transformer check out OK..
Thanks
Skip
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That is a real neat one Skip!
Times I have been electrocuted in 2021
As of 1/01/2021
AC: 4 DC: 1
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Hey Skip, is that a HP 432A power meter on the shelf above the radio? Looks very familiar.
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Yes its a HP 432 A Power meter with a 478A termistor mount. When I worked for one of my last company they were throwing them away because they deprecated to 0. And replaced by HP 436 A's. They let the employees pick what they wanted before going to dumpster. Got a HP 141 Spectrum ANA that way to.. Both work Perfect..
Skip..
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Ok Just looked at my speaker.. The Front doesn't quite look right...
[Image: http://i292.photobucket.com/albums/mm38/...r2v2uo.jpg]
schematic show's T1
[Image: http://i292.photobucket.com/albums/mm38/...lunblr.jpg]
Primary reads 536 ohms.. Sec .6 Ohms.. The .6 ohms are measured at here .. 2 terminals that go to speaker..
[Image: http://i292.photobucket.com/albums/mm38/...3de2lb.jpg]
Skip...
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That's great, at least they let the employees have that test eq before junking it. Too many companies just get rid of things like that without thinking about their own people who could use them.
The 432A is really nice because it is a primary thermal transfer standard, allowing you to accurately measure RF by substituting easily measured DC voltages and currents. The government NIST lab still uses these meters as calibration standards. The last recent price from Agilent for the meter alone was over $10K.
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How much resistance do your test leads have? Its pretty difficult to measure 0.27 ohm accurately unless you can null out your lead resistance or use a 4 wire measurement.
I doubt there is anything wrong with the output transformer. The secondary is wound with relatively few turns of heavy wire which does not typically go bad.
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Agreed.. My leads have .10 Ohm Resistance. And I measured .7 ohms so Real reading is about .6 Ohms.
I didn't like what the front of speaker looked like.. So that's what I was questioning..
Skip...
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(03-15-2017, 08:51 PM)vecher Wrote: Agreed.. My leads have .10 Ohm Resistance. And I measured .7 ohms so Real reading is about .6 Ohms.
I didn't like what the front of speaker looked like.. So that's what I was questioning..
Skip...
It isn't really anything that some contact cement or fabric glue couldn't repair, sometimes the edge of the cone will lift off like that. If it is lifting off anywhere else around the rim of the basket it would be best to shim the voice coil first before trying to glue it back down, to stop things from shifting.
Regards
Arran
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Ok Houston we have a problem.. Completed the Recap and Resistor replacement.. Powered up and at 115 Volts reading .40 Amps Looked good..
But when trying to receive stations I get scratchy sounds .. I did RX a strong station.. I measured the tuning Cap to ground and it reads about 6.5 Ohms.. I think I need to take Cap out for a good cleaning..
What should I use to clean Cap.. With out damage.. After I get it out I will measure it again before Cleaning to see if I still get a Ohm reading..
Skip..
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Maybe not if you look over the diagram you'll note that the tuning cap has a coil in parallel with it so what your ohm meter is see is the inductor and not so much the cap. Now it you disconnect the wires from the cap and measure a low resistance then you've got a problem.
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
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