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PHILCO 37-660 - Printable Version

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RE: PHILCO 37-660 - Arran - 06-13-2026

An easier way to explain it is that a 5U4 has the same pinout as a 5Y3, and I believe that a 5X4 may have the same pinout as a 5Y4, both the 5U4 and 5X4 are successor tubes to the 5Z3, which is pretty much a heavy duty type #80.
Getting back to this 37-660, I would go by the diagram inside the cabinet, I can't read the code number on the blue label but I'm guessing that this may explain why the version linked too was a mirror image. The set linked to also uses a 5Y4 for a rectifier, why I don't know, hopefully the rest of the power supply matches the specs of that tube rather then the 5X4 or it won't live very long.
Regards
Arran

RE: PHILCO 37-660 - MrFixr55 - 06-13-2026

Edited at 0822 EDT to add content.

Hi Arran,

Yes, you are correct. 5U4 and 5Y3 have same pinouts, 5X4 and 5Y4 have same pinouts. I used 5X4 because it looks like that was what was in the socket. There is also a discrepancy between the pictorial and schematic in the service document. The chassis is "mirror image" because the figure in the service document is from the underside of the chassis.My detailed (labrynthian?) explanation of locating sockets was in case someone actually did make changes.

Yes, the diagram should be correct. The Service info in our library is also correct as to location of the tubes. the 2 6F6s are closer to the transformer than the 6J5 which is closer to the 1st Audio tube. This all makes sense if I were to lay out a radio. I wouldn't want to put a high impedance voltage amplifier next to a power transformer. My previous response also offered a theory as to why it actually worked with a 6F6 and 6J5 swapped.

RE: PHILCO 37-660 - georgetownjohn - 06-13-2026

Arran and Morzh thanks so much for the help. While I could not get in the tangle of parts and wires to verify the plate wiring of the 6F6's , I did pull info for pin numbers of the 6J5. On it, pin 4 and 6 are idle. I then looked inside at that socket that is labeled as the 6J5G on the tube label diagram in the cabinet and it matches! Sooo, I will make sure the tubes are installed per the cabinet diagram this time. By the way, the label looks like it says code 121. Also Service Bulletin 257 states that the correct rectifier should be 5X4G as the label in my cabinet shows. I have ordered a 6J5g replacement for the broken tube--they are not cheap! Thanks again to all for the help, John

RE: PHILCO 37-660 - morzh - 06-13-2026

While it is good, you cannot reply on unused pins on tube panels, shown unused in teh sch, being empty of wires.
They often use them as solder posts for unrelated circuitry.

RE: PHILCO 37-660 - georgetownjohn - 06-14-2026

Does anyone know what rubber parts I should order for the 37-660 and where to get them? These go on the inside base of the wood cabinet and cushion the bottom of the chassis. There are 4 of them and they fit in round cutouts on the inside of the cabinet base. They also have holes in the center of them where screws enter from the bottom of the wood cabinet to hold the chassis.

RE: PHILCO 37-660 - Joe Rossi - 06-14-2026

John, Renovated Radios has all the rubber pieces for your Philco.  Joe

RE: PHILCO 37-660 - georgetownjohn - 06-15-2026

Hello PHORUM members.  I am preparing to install the safety caps I ordered and am trying to figure out if that they will replace what I beleive the orginal owner installed using conventional caps.  Hopefully I am correct in thinking those are the ones that I should replace with the saftey caps accross the line.  I have attchaed 3 photos to help with my question. Thanks, John

RE: PHILCO 37-660 - georgetownjohn - 06-15-2026

Thanks to Joe Rossi for the reply on rubber pieces. I am awaiting reply from Renovated Radios as to what part number since I do not see one listed for the 37-660 and it looks like it could be one of two theyhave for Philco. My originals are so distoted, I can determine what their orginal size really was. I do not see a part# for them on the parts list probably because they were considered as misc.

RE: PHILCO 37-660 - morzh - 06-15-2026

The tell-tell sign is, they go from each of the 110V AC input wires (may be before or after power switch, does not matter, depends on the radio) to the chassis.
If those do, then those are the ones you replace.

RE: PHILCO 37-660 - glyphmon - 06-15-2026

John,

I'm not sure about your model, but what I did with identifying the rubber pieces was to just measure the outer diameter of the holes on the cabinet, and then the shaft size of the screws that feed through them.

For my 37-620B, I think this was the part I ended up ordering:
https://renovatedradios.com/products/cw-447

Best wishes,
Roy

RE: PHILCO 37-660 - georgetownjohn - 06-15-2026

Morzh, thanks as always for the saftey cap info. Thanks to Roy for the reply, yes, I measured the hole and found that Rnovated Radios part CH4 should be the one so I ordered 4 of them. The one that has a screw and sleeve in it that goes in the bottom center rear of the wood cabinet and then up through the chassis is still good so I am ok there.,, John

RE: PHILCO 37-660 - radiorich - 07-04-2026

Hello John,
Yes, I have ordered that same part from Renovatedradios and what Morzh said as looking at your photo they do tie to the chassis at one end .

Sincerely Richard