hello:
I have a speaker from a Philco model 76 with an open field coil. I am considering replaceing it with a PM speaker. Can you tell me the resistence of the field coil? Thanks again
Posts: 13,776
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Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
3200 ohms. Speakers for this set are not hard to find; also, have you considered either having your field coil rewound or rewinding it yourself? Could be that the break is close to the end (not likely, but a possibility)? Just food for thought. If you do go the PM speaker and resistor route, use a 25 or 50 watt resistor - the resistor will dissipate around 10 watts or so, but it will also run hot. The higher wattage rating will compensate for this.
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Ron Ramirez
Ferdinand IN
Hi Ron-Thanks for the fast reply. I was considering the resister and pm speaker as I am not sure the radio is going to be one that should be repaired. I took pictures after I removed the metal plate from the bottem of the radio. I am glad that I did as no one would believe the metal objects I found . Nails- screws-bolts-long apolstering pins-two screen door hookswith eyescrews and various other. I may be able to find a choke that I can use with a pm speaker so I can see what all I will have to replace. Thanks again
Hello-another day
I connected an old xformer in parallel with the open field coil connected the secondary of the original output xformer in parallel with the voice coil of a PM speaker. I connected antenna to the grid cap of the detector. Placed a 1 amp fuse in both legs of the AC and pluged it in. I received one strong local station. I had installed two 2 MF electrolitics. One on either side of the filter chock.
It looks as I am going to need several parts.The BC resister will need to be replaced-part# 3865 another resister part #3864 should be replaced. If I can find all the parts I will replace the speaker also.There is a condenser part #3584-B that is bad and I do not know what it is. It is not listed in Chucks book on capaciters and the value is not shown on the schematic.It is hooked to the 4th R> F> transformer.I had to disconnect it before I could receive anything. The 4th RF transformer may be bad Get into that tomorrow. I think I will place a wanted Phico 76 for parts.Thanks again