I am a newbe, whom aquired a Philco Model 50. When I received it, the volume control was in 2 pieces. I aquired a used one from the U.S. I installed it the exact same way as the old one, making note of the wiring, as a dual potentometer. Problem is, that I have no noise (not even a hum out of the speaker). The filliament voltage is ok, all tubes light up,the tubes test ok in a tube tester. I have replaced all filter caps, as well as all paper caps, and checked all resistor values.Only resistors and caps I did not replace, are the enclosed ones .I checked the B+ voltage, and it is 317 volts measured at the filter capacitor to ground. The output transformer measures 354.0 ohms, and the voice coil 1,195.0 ohms. Can anyone give me some advise, or steer me in the right direction. Thanks
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Hi
Please refer to the schematic here.
You mentioned you did not replace the "enclosed" caps...do you mean you did not replace the caps in the rectangular metal can, or you did not replace any of the caps in this or the bakelite blocks?
All of the paper and electrolytic caps must be replaced, even those in the bakelite blocks and the metal can.
Doublecheck your wiring.
Also note that the dual ganged control in the 50 is not the same as used in Models 20, 70 and early 90. The 50 needs one that has 1750 ohm and 5000 ohm sections. If you are using a dual gang control from a 20, 70 or 90, the set will not work as that control has 250 ohm and 5000 ohm sections.
--
Ron Ramirez
Ferdinand IN
Thank you Ron for your reply. I have not replaced the backelite blocks or the metal can (i was hoping it would not be required) but it looks like this will be my next venture. As for the dual pot, I got it out of another model 50 (used for parts) and was tested by a reliable source. I want to thank you again, and I will carry on! May be in touch again as I progress.
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Ron Ramirez Wrote:Hi
Please refer to the schematic here.
Ron,
I noticed that your schematic as well as the Beitman's don't list any voltages.
Voltages can be found on Rider's page 1-15 found here:
http://www.nostalgiaair.org/resources/S0...PHILCO.htm
Carl
Northern Panhandle, WV
Thank you both for your excellent help. Everyone is so helpful! You were right Ron, I removed the filter capacitor can (holds the 5 capacitors) and it was entirely corroded. I am now in the process of tracing wires (as the colors are not there anymore) and install new caps. Again, thanks for your support.
I am in the process of replacing all caps on this radio. I have come across some bakelight enclosed ones. Is there any way to actually read these, that is which end is positive, and which is negative? There is a center post in the middle, and a terminal on each side. I am familiar with the old paper, mica, electrolytic, but not these. Can anyone help me out? Thanks
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Hi
They are paper caps inside a bakelite housing. Non polarize. Typically but not all the time you will have two caps inside with two ends tied together connected to the chaiss ground though the mounting screw. The two ends will connect to the other two terminals on the bakelite block and thus making connections to the circuits in the radio. Please check diagram to make sure what the values are and how they connect to the set.
Terry
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
Thanks so much for your help Terry! I will attempt to do a replacement with some new ones.
Doug
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I did notice that one of the blocks has a 150 ohm resistor and a cap in it.
Terry
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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Howdy,
Go to the following web-site for the values of each bakelite block; http://www.philcorepairbench.com/bblokcap.htm There is also how-to instructions in refurbishing them.
Joe
Joe
Matthew 16:26 "For what does it profit a man if he gain the whole world, yet lose his own soul?"
I have now replaced all caps (including backalite ) plus resistor in one of them. I have checked all resistors with a ohm meter. As well, all tubes have been checked with tube tester. All tubes light up, so the filiaments are ok, as well as checked filament voltage of 2.5 volts.Thinking maybe my speaker is faulty, (as I get nothing out of the speaker) I measured the resistance on the outer connections of the speaker at (1194 ohms) and the inner at 353.6 ohms. ( Note I had the speaker disconnected from the radio when taking resistance measurements). As far as voltages across these points, I measure 57 volts dc across on the outer pins, and 14.2 Volts dc on the inner. If anyone has a suggestion on where to start next, it would be greatly appreciated!
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Ok so how much voltage do you have across cap #32?
Terry
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
Thanks for your help Terry. I just measured it and I measure 374 volts DC. This was across the electrolytic #32
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Two things you may want to check. First with the radio powered see if a metal non magnetic screwdriver is attracted to the back center of the field unit. Second with the radio off check the connections from the secondary of the output transformer and voice coil winding. You will have to unsolder 1 lead. Resistance of each will be around 1 ohms.
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