Philco 610 transformer open
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I recently recapped a Philco 610b tabletop unit I acquired a year ago. Being a novice, I waited until after recapping to check the coils. The coils are fine. But I found the primary of the main transformer is open. My tube tester also found zero conductance on three of the five tubes. I suspect the radio experienced an "event."
I can replace the tubes. But what are my options with the transformer? Is it rewindable? Are there replacements (PN 32-7381)?
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You need a SE (single-ended) transformer for a 42 tube with about 1:100 turns ratio.
Try Oldradioparts.com
I looked at Hammond 125 SE series, they do not provide 1 Ohm to 10kOhm, so they do not match well.
(This post was last modified: 10-22-2014, 09:30 AM by morzh.)
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1345-213 OUTPUT UNK 22E4 SP, 100:1 RATIO, 5-6 WATTS, FIG 3, TOP SEC LUGS, PRI 3"L,U 1 2 3/8 2 0/0 1 1/4 2.25
This is Fig. 3
http://oldradioparts.com/2a23g2.jpg
http://oldradioparts.com/2a23dfl.txt
Unfortunately there is a minimum order of $20.
(This post was last modified: 10-22-2014, 09:34 AM by morzh.)
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Thanks. I see a 1450-703 used piece in the list that looks to be available. I may as well get the tubes from there as well.
(This post was last modified: 10-22-2014, 10:02 AM by Kestas.)
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hi kestas
is it (PN 32-7381)? or pn 32-8137n
sam
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(10-22-2014, 09:11 AM)Kestas Wrote: .....But I found the primary of the main transformer is open........Are there replacements (PN 32-7381)?
I think there are two different transformers being discussed here. Morzh is referring to an output transformer and I think you might be referring to the power transformer. It might be a good idea to clarify exactly which transformer you're looking for. PN 32-7381 is the power transformer.
John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
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Oops, my bad, thought we were talking of the output transformer.
Disregard.
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John, I was thinking the same thing. If it is the power transformer, depending on how you tested the primary, it could be a defective on/off switch.
Best, Jerry
A friend in need is a pest! Bill Slee ca 1970.
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Kestas
Did you check your primary with across the AC plug or actual transformer wires?
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I checked many different ways, but finally I checked after the switch and power cord - directly on the wires coming from the transformer. There was no deflection on my ohmmeter.
And yes, we're talking about the power transformer. I'll verify the number off the part itself when I get home.
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Sounds bad Kestas, nothing to lose removing and taking off the end bells to pray that it is a bad connection coming from the external wires to the coil. Philcos generally have good power transformers unlike the Zeniths that seem to be under rated and prone to opening.
A friend in need is a pest! Bill Slee ca 1970.
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The part itself is stamped #32-7381N. It looks like the event took out the rectifier tube (80), detector/oscillator (6A7), and IF tube (78 ). Two of them have open filaments.
Also, the resistor for the rectifier emitter - R39, 10k ohm, 2W - looks burnt, but ohms out okay within spec.
I'll poke around some more before ordering the replacement part.
(This post was last modified: 10-22-2014, 09:11 PM by Kestas.)
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Kestas,
At this point it might pay to try to look for another chassis (or for a similar one) as a donor or direct replacement.
However, from the same website:
1450-703 POWER PHILCO 32-7381 340-0-340V @65ma, 5V 2A, 6.3V 2.2A, MODEL 610/620, FIG 2,U 1 3 1/2 2 3/8 3 0/0 15.75
http://oldradioparts.com/2a23efl.txt
See if this is what you need.
PS. If I were you, I'd call him right now.
(This post was last modified: 10-23-2014, 09:56 AM by morzh.)
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