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thats odd,,
the right hand side of the transformer you posted shows .8ohms.,,, yes at the speaker end its 5 ohms.
its odd you come up with a resistance value that ***IS*** shown on the diagram.
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(02-15-2019, 06:59 PM)jcassity Wrote: thats odd,,
the right hand side of the transformer you posted shows .8ohms.,,, yes at the speaker end its 5 ohms.
its odd you come up with a resistance value that ***IS*** shown on the diagram.
Stranger things have happened, I've actually fixed a radio or two.
The green wire isn't absolutely necessary should work without it. It's part of a negative feedback circuit to improve audio clarity, except for higher end sets few have it.
Tom
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LOL,, yeah well i guess at this point i tend to get lucky when they end up working for me.
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Sometimes when I get one working I say to my self " Blind pig finds a acorn "
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City: Ranger
State, Province, Country: Ga
(02-15-2019, 06:59 PM)jcassity Wrote: thats odd,,
the right hand side of the transformer you posted shows .8ohms.,,, yes at the speaker end its 5 ohms.
its odd you come up with a resistance value that ***IS*** shown on the diagram.
Im measuring .9 ohms at the voice coil where it should be 5 ohms, so i've ordered a new output transformer, fingers crossed this fixes my problem.
Ryan
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Bear with me, I'm fairly new to radios. I do have 5 ohms at the speaker, ( i was thinking the 5 ohms should be the secondary of the transformer) so with that I hooked up a second audio source while using the radios field coil and the speaker worked. Second problem was I was using a EICO s.g. I picked up not long ago and it was not working properly, I hooked up the sg-8 and I do have a signal on pin 4 of the 42 tube but its very faint. SO perhaps the output transformer is bad and not boosting my signal? or there is another problem; Im thinking there is another problem because there is no signal from the volume pot or strait to the tuning condensor. Ill start checking voltages
Ryan
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City: Bellmawr, NJ
I had something like this happen,,,But ,,the transformer and speaker field. were wired WRONg in the plug ,,,Backwards,,,and still have a little tiny amount of sound,,,,till ,,I traces it all back to the tubes,,
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I believe I have found one of my problems (circled part) Instead of the 6.4 ohms, I'm measuring 22k... in the 1st IF can, Im not sure how to go about correcting that yet. I've decided to trace every wire back on the print and check every resistor along the way, I,ve found a few pretty far out of spec but not sure if that would cause my problem. But im certain that IF would. Any suggestions on repairing are welcome. TIA
Ryan
(This post was last modified: 02-19-2019, 09:20 PM by rperry.
Edit Reason: mistype
)
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If winding in IF transformer is open generally they require replacement, though sometimes brak is visible and can be repaired.
Tom
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Most likely than not the winding is open.
It is worth opening the can and seeing if it could be repaired before embarking on a search for a spare IF can.
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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After a 2 week break away from the radio with family matters, im back on it, I found the break and I took a couple wraps off the IF transformer that was reading open. Im now reading 7.4 ohms through the transformer instead of 6.4 ohms, hopefully this wont effect it much?
I am now getting a clear signal on pin 4 of the 42 tube but not one on the middle pin of the volume pot.
Ryan
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There was a bad ground on the 6f5 (thanks Terry for the help!), once that was fixed there was a awful squeal on the speaker. It turns out the humbucking part of the circuit that was disconnected originally was for a reason, once I put it back the way it was the squeal was gone and I started receiving. Time to do an alignment and get to work on the console.
Ryan
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City: Roslyn Pa
Glad to hear ur making some more headway.
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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Finished.. I had to use some darker toners due to heavy stains on the top and chipped veneer repair.
Ryan
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