Posts: 36
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City: Belleville, Arkansas
I would like some opinions on this speaker. I bought this off eBay and it was listed as a Philco model 20 speaker, but I am not sure that is the case. The Output transformer is stamped 2766 J. I looked up 2766 J on the Philco library and it says it is for Philco Models 40,41. It also says it has a field coil of 3 ohms.
I was hoping to re-cone this speaker and use it with a Philco 21 chassis I am working on. I am thinking since the field coil is 3 ohms I can use a 3k resistor in series with it and still use this speaker.
I guess my main concern is that it seems odd to find an oddball speaker that was used in DC only sets.
I have attached some photos of the speaker.
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City: Ferdinand
State, Province, Country: Indiana
Looking at the
Philco Speakers file available here:
https://philcoradio.com/phorum/showthread.php?tid=215
we see that output transformer 2766 was also used on speakers K and K-2.
The speaker used in models 40 and 41 was "J". That is a 10-1/2" unit with a 3 ohm (!) field coil.
Speaker K and K-2 are 8 inch units with 3100 ohm field coils. Speaker K was made for models 20 and 21; K-2 was used in the early version of model 90 with two 45 output tubes.
So...assuming your speaker's field coil is OK and measures around 3100 ohms, and assuming the 2766 output transformer is OK, you should be fine. Your speaker is clearly an 8 inch unit.
Measure - don't assume - to be certain.
--
Ron Ramirez
Ferdinand IN
Posts: 36
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Joined: Oct 2014
City: Belleville, Arkansas
Thanks for the advice Ron!
The field coil actually does not give an ohm reading. It appears open when measuring across the two green thick wires. I actually had a suspicion it might be open. I will further disassemble the speaker and see if I can get to the field coil.
If so, I may try and fix it.
P.S. The Philco 80 clock you sold me a while back still sits on display in my house. I get a few comments about it!
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Well, it's easier fixing 20's field coil as one does not have to press out the pole. Same K speaker from 70 and 90 does not have the nut and the pole is pressed in.
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.
Posts: 36
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City: Belleville, Arkansas
Good to know, morzh!
I drilled out the rivets on the output transformer and removed it. As a side note, I actually think it is bad as well. I removed some of the wrappings on the field coil and was able to find two small enamel wires poking out! I am hoping in the next couple of days to have some more time to work with the field coil and see if I can get it fixed!
