I just recapped this radio. When I turned it on had a lot of static especially when moving the speaker wire. While moving the speaker wire I touched something on the top side of the chassis and got a shock. Now the unit is silent. Im still in my rookie year on trying to repair old radios. Can anyone tell me where to look for the problem? Thanks
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Good morning Ralph and welcome,
Have a good look at the speaker wiring and check worn insulation. Most of of the time it's pretty tatty. If so rewire as there is about 250vdc on those wires and can arc to the chassis or give you a good jolt! And if it is arcing will make static in the speaker.
Thanks, I do have one of the speaker wires in bad shape. I connected a temporary wire till I get some more to replace all 3. Im not picking up any channels yet. I'm going to investigate that.
After you sorted the wire touch the grid cap on the 75 tube. It's next to the 42. It should let out with a loud buzz!! If so then hook your signal generator up to the grid of the 6A7. Set the sg for 460kc w/tone and see if it will pass a signal thru the IF stage. If you'd like a brush up on how the superhetodyne works:
https://www.youtube.com/watch?v=hz_mMLhU...onnections Report back with your findings.
Hi Terry,
I was working on this radio over the weekend. I had the load buzz before I changed the speaker wires but not now.
While it was on resistor #22 on Philco 60 schematic a 10,000 ohms was running hot and metered out at 14,000 so I replaced it with a 10K resistor. The 10K resistor cooked immediately. What do you think cased the problem? Also on tube 42 sometimes I will get over 900V other times it will be in a normal range. Does that make any sense to you?
Thanks, Ralph
The 60's are coming out to blume lately.
Philco Service Bulletin 164A.pdf (philcoradio.com)
My best guess is that no good deed goes unpunished. When you saw the opportunity to replace an out of tolerance resistor you did. But you did with a 1/2 w model when it needs a 2w or so. It ate it for lunch...
As for the 900v not sure what's going on short of have the meter set on ac volts and you are reading the ac spikes across the pri of the output transformer.
I replaced the 10k 1watt with a 2watt and that one overheated also. Can I go higher in the wattage?
After further investigation I've found that it is suppose to be a 1/2w resistor as per the part #.
That would imply that there is a short to the left of #22. Would measure the resistance from 20A to the chassis with the 6A7 in and with the 6A7 out. If all is ok should see high resistances. Check your soldering work for shorts to the chassis ( near #22 ).
Condenser bank 20 hosed? That would cause a lot of issues
I am currently working on a 60B also, I just finished the electrical and alignment, works great!!
Be sure to check and see what run your radio is, mine is the last run, run #7 also has the square shields.
The resistors and caps have changed, some have been droped, others added; See schematics and changes here:
https://philcoradio.com/library/index.ph...-model-60/
Also bulletin 164 may not match your radio!! is does not match mine!
Mine is a 60B with square shields. I'm not sure if it is a run 7. On run 7 #22 10K resistor was eliminated I haven't yet figured out why it keeps burning up #22.
How do I figure out what run is mine? In the meantime I'll check the resistance in and out of 6A7.
A local vintage radio restorer has been helpful. My first try at vintage radio Repair was a Zenith 970 I got it 90% there but couldn't get it to play. The local restorer finished it for me and said the schematic was wrong. I'm afraid I may be following the wrong run on this Philco 60B. My other set back is I have been in the restaurant business for 50 years and not much experience in this.
I bought a EICO 320 signal generator on EBAY. When I got it we found that the 6X5 tube killed the power transformer. I think I have it properly repaired. That being said I have never used one and the local restorer is not available to help with advice.
Ok, you have square shields, same as mine, thats the last Run, there is no resistor #22.
The 39K resistor I had to replace with a 2W because it got hot.
You need to be using the last schematic on this page:
https://philcoradio.com/library/index.ph...-model-60/
DO NOT use any of the previous schematics.
Also a couple of the bakelite caps changed too.
Also capacitor can #20 should have 4 wires coming out of it NOT 5 if it is Run 7.
Thanks Lewis, I’m working on it today. I can’t find this resistor on the schematic. It was connected to pin 5 on tube 78 the resistor is yellow violet orange and gold.
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Let me see if I can untangle your mystery.
The tube socket in the middle of the pic, the 7pin one is the 6A7 not the 78. The 78 uses a six pin socket. The 47,000 ohm is pretending to be #19 which is fine as long as it's with in spec. The loose end goes to chassis gnd.
You could have wired at pin 3 of the 6A7, #20A, ungrounded side of #19, and the left side of #22.
On the 78 (IF amp) the cathode and suppressor grid probably are connected together. If you measure the resistance from pin 5 the the chassis you should about 200 ohms. The later models have the suppressor grid grounded separate from the cathode. The 78 cathode is connected to the 6A7 cathode so they could use just one resistor vs two.
My 60B is Run 7 on the schematic #19 changed from 51K to .1MEG Thanks for the help