The PHILCO Phorum

This Philco resistor measures open and I'll be replacing it in a Silvertone I'm working on.  Distance between the terminals is 1 1/2".  Is this a 1 watt or 2 watt resistor?  Also, does the 4000 in the part number represent the ohms value?  If not, what is the ohms value?

Thanks,
Larry

For your reading pleasure. Hope this helps. David    https://philcoradio.com/library/index.ph...t-numbers/    other   https://philcoradio.com/library/index.ph...resistors/

That blue resistor is a 10 watt wirewound. As it is not original to the radio, it is unknown what the wattage of the original was. I would try to find the service info for your Silvertone radio and see what the resistance value and wattage should be.

Perhaps someone here has info on what the specs are on that Philco part number?

Hi Larry, I, probably like you, read through that whole section on Philco resistor part numbers, but realized that the numbers on that wirewound ceramic resistor don't match anything given there. Were I in the position you are, I would look to the schematic for that particular Silvertone model for the value. See where the resistor connects in the circuit, then find the resistor in the schematic which matches it. This should show the resistance value in ohms. (My guess is that it is 4K). If there is a parts list in the pages for that model, it should list both the resistance and wattage. If not, how the resistor is used in the circuit should be your guide. If you can tell us the model, so we can look up the repair information in Rider's, perhaps we can be of more help.

Thanks, guys.  The side of the resistor that you can't see in my first photo has some wound wire visible (see photo below).  I cleaned the wound wires and found a distance where I had continuity between two points.  Those points are marked by the small black markings and I read 90.1 ohms between the two.  Those points are 3/4" apart.  The distance to the inner edges of the terminals at each end is 1 1/4".  Based on that I figured the full resistance should have been approximately 150 ohms.  With Mondial's 10 watts, I now know what I'm dealing with.  

This resistor connected between pins 3 and 7 of the 5Y4 tube.  The schematic is included below.  I'll have to do some more head scratching on this but I suspect it replaced R13 which is a 160 ohm resistor rated at 1 watt per the parts list.  The radio is a Silvertone 4663.

Thanks for all the quick replies.
Larry

Here is the Nostalgia Air file of the Rider's pages for the Silvertone 4663..
http://www.nostalgiaair.org/PagesByModel...017181.pdf
Oddly, the schematic does not match the one in your picture. In any case, neither schematic shows a resistor connected as you describe.

There were two chassis used in the Silvertone Model 4663.  Nostalgiaair and Rider's both have schematics of chassis 101.471 made by Colonial.  My 4663 has chassis 100.158 made by Stewart Warner.  The only place I've heard of to get that schematic is from the inside of the cabinet.  As you saw, my cabinet schematic is incomplete.

I will have to draw the circuits associated with the 5Y4 as this radio now has them and see if I can understand what has been done to it.

On many Silvertones I have seen they glued a schematic underneath, nice touch. They had so many manufacturers and so many radios what a record keeping problem. They supplied the masses along with all the other store brands and Emerson.

Paul

I found some higher resolution photos of the label for your radio on ARF. Looking at the parts list, there are only three resistors which are high enough wattage to be the one pictured. One is R4, a 15K, 2 watt resistor. Another is R13, a 160 Ohm, 1 watt resistor. The third is R16, a 15K, 1 watt resistor. Looking up the pinout of the 5W4 rectifier...



... we see that pins 3 and 7 are NOT USED in this tube, so it is possible that these terminals were used merely to mount this resistor with leads going to another part of the circuit. That said, and given the size of the resistor, and your measurements, I am tempted to say it is probably R13, the 160 Ohm, 1 watt resistor. Trace out any other connections to pins 3 and 7, and see exactly how this resistor is connected. Then you can be sure. Modern resistors are much smaller than their old counterparts. You will be able to buy a 3 watt resistor that will be much smaller than what you have now.

Thanks, Mike! I haven't had a chance yet to start tracing out the circuits.  Wish there were wiring diagrams.

Larry

The best I could find, hope it helps. David[attachment=26220]

Looking at 6K7G vs 6U7G both have a grid cap and the pin out is the same. Having worked on a Silvertone radio a few years back would not be surprised if Sears got a real good price on the 6U7G tubes. David