Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12, 2025) x

Thread Closed

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:
[-]
Recent Posts
54C Complete Teardown/Rebuild
Hello Roy, here is this one sincerely Richardradiorich — 12:45 AM
54C Complete Teardown/Rebuild
Richard, Had grabbed it already but thank you just the same.  I find myself wanting to find some way to block out the...glyphmon — 12:03 AM
54C Complete Teardown/Rebuild
Hello roy, here is a link to the schematic . Sincerely Richardradiorich — 11:54 PM
54C Complete Teardown/Rebuild
Richard, The Silvertone 2014 also is a transformerless set, so I am incorporating a 1:1 600 ohm audio isolation transfo...glyphmon — 11:37 PM
Preliminary work on wife's Silvertone 2014
Did an alignment today which was interesting.  IF alignment went great, almost all was already spot-on.  Adjusting on th...glyphmon — 11:35 PM
54C Complete Teardown/Rebuild
The main problem with adding a Bluetooth input is that this set lacks a traditional power transformer to isolate it from...radiorich — 11:19 PM
54C Cabinet Refinish
I started stripping this cabinet before it got super chilly out because I knew I wasn't going to be able to work on ...glyphmon — 11:18 PM
54C Complete Teardown/Rebuild
While I'm waiting to wrap up the final steps on my wife's Silvertone 2014, I started disassembly on the next project.  O...glyphmon — 11:07 PM
Preliminary work on wife's Silvertone 2014
Hello roy, that great news glad it worked out for you !! Sincerely Richardradiorich — 10:50 PM
Preliminary work on wife's Silvertone 2014
Safety caps arrived today.  Soldered one in and had a successful first power-up.  No magic smoke escaped and it tunes in...glyphmon — 09:53 PM

[-]
Who's Online
There are currently 1855 online users. [Complete List]
» 1 Member(s) | 1854 Guest(s)
Avatar

>