Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

repairing Philco 37-620
#1

I'm repairing a 37-620 that belonged to my father, but hasn't been turned on in over 40 years. I last repaired it in 63, (replaced electrolytic to get rid of a bad hum) and it worked for a couple of more years. By following articles in your excellent web site, I have replaced all the paper caps and resisters that were out of range and replaced a defective on/off switch and an open output audio transformer and much degraded wiring. I was able to get the original parts from Gary at Playthings of the past. I got a schematic for this set from Chuck Schwark, Grommets from Ed Schutz, and a new Dial from Mark Oppat. Thanks you guys for a rapid response to my orders. I next built a dim light rig (also found on your site) for turn-up. Progressed from a 15 watt bulb to a 100 watt bulb and am now receiving a couple of local stations with the 100 watt bulb in-line. Doing voltage checks, I find that with the 100 watt bulb in-line I have 97 volts AC being applied to the radio input. With this low line voltage, all my plate voltages that should be 240+, are around 110V, and my 150V are around 80V. Are these voltages ballpark under this set up? I want to go direct with out the in-line 100 watt bulb, but thought I would seek a little advice first.
Second question, according to the alignment instructions, they use a Philco Model 025 Circuit tester, and connecting it between the plate and cathode (grounded cathode) and using the 0-30 volt range. Does anyone know what this meter was. I have 240v on this plate to ground. Whats with the 0-30v range on the test meter. Thanks in advance for any response, also for this site. I enjoy reading the many great articles, they bring back many good memories and have me thinking if electronic circuits I haven't thought of or even heard about in many years. Mike




Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
Philco 60 Squealing
Wavetrap no longer matters.morzh — 05:19 PM
Philco 60 Squealing
Rod, I had checked out your suggestions but did not help. I did solder the ground rivets to the chassis as Chas suggeste...dconant — 04:52 PM
37-690 Bass Choke Replacement
Yeah, I know, Mouser and Digikey don't have "big iron" components. For some reason Philco was messing with the...Radiodial — 04:25 PM
37-690 Bass Choke Replacement
Yes, I just had to deal with that while repairing the 37-604 Philco. Exactly that value choke was gone. And the current ...morzh — 03:52 PM
37-690 Bass Choke Replacement
Ah, now where to find one. I've into this before on smaller sets, I now recall. Hammond makes one that is only rated...Radiodial — 03:27 PM
Philco 38-7 Speaker
Ask the admins to put them together. As for the renaming, while inside the thread, you simply press "New reply&quo...morzh — 02:23 PM
37-690 Bass Choke Replacement
This is the parts catalog. 32-7528 choke is 65H, 10mA, 2,250 Ohm inductance. Find a suitable one.morzh — 02:18 PM
37-690 Bass Choke Replacement
While troubleshooting the no bass amplification issue, I think I found the culprit. The choke #104 is reading 164K ohms....Radiodial — 01:42 PM
Philco 60 Squealing
Your IF transformers are tuned to the resonant frequency they were designed for. When you observe the bell curve they di...RodB — 01:35 PM
identify very thin wire for replacement on 37-640
Thanks so much for your help!  I really could not have gotten this far without the kindness of you and other members.  T...georgetownjohn — 11:50 AM

[-]
Who's Online
There are currently 4679 online users. [Complete List]
» 1 Member(s) | 4678 Guest(s)
Avatar

>