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

Philco 37-62 head scratcher
#1

Hi Everyone...my first restoration project here. Its fun working on the set until you change everything that is supposed to be changed and its still doesnt work, its still fun, but it leaves me scratching my head more. right now the unit hums when the volume it turned up, but no stations. Ive touched the grid of each tube and it buzzes on the 2nd detector/1st audio 6Q7G tube and none of the others. This I assume would indicate that audio section is good. (buzz in fact can be quite loud) I've replaced 3 tubes (det/osc, if, and rect) all bakelite and tubualar caps. I have inspected 1st and 2nd IF coils...wires are fine but none broken and contacts are good.
I can only think of one thing suspect at this point and would like to hear some feedback before prodeeding further. det/osc and IF screen grid voltage reads 125 volts... diagram indicates it shoud be around 85 volts. Resistor on the screen grid ((part 11) should be 25 K ohms, color code and markings indicate that is is a 15K ohm resistor. (meter reads about 18K) Interestingly there is a change note with the schematic that states that the resisitor should be changed to a 32 K ohm to eliminate oscillation. Why would there be a resistor of that value there beats me... or am I sniffing too much solder? could this value resistor and high screen voltage cause the hum and no receive?

I feel like im easter egging here but hope this makes sense, feedback appreciated. Thanks in advance


Messages In This Thread
Philco 37-62 head scratcher - by Guest - 02-13-2009, 09:59 PM
Re: Philco 37-62 head scratcher - by exray - 02-13-2009, 10:56 PM
Re: Philco 37-62 head scratcher - by Guest - 02-13-2009, 11:16 PM
Re: Philco 37-62 head scratcher - by exray - 02-13-2009, 11:47 PM
Re: Philco 37-62 head scratcher - by Guest - 02-14-2009, 12:19 AM
Re: Philco 37-62 head scratcher - by Texasrocker - 02-14-2009, 03:06 AM
Re: Philco 37-62 head scratcher - by exray - 02-14-2009, 09:21 AM
Re: Philco 37-62 head scratcher - by Guest - 02-15-2009, 07:50 PM
Re: Philco 37-62 head scratcher - by exray - 02-15-2009, 07:58 PM
Re: Philco 37-62 head scratcher - by Guest - 02-15-2009, 10:48 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
IF can wire size and Rubber mounts?
Arran If the wire inside cans is the gauges you mentioned, the sole reason for that would be mechanical, to stiffen t...morzh — 12:56 PM
12' Philco
Rod, Yes, I know, but the Giant Philco is not around anymore either, so I go by whoever was alive fairly recently. H...morzh — 12:54 PM
Hickok AC51 tube tester
Absolutely no one is going to reverse engineer that circuit. Even the iron core is missing.RodB — 10:37 AM
IF can wire size and Rubber mounts?
Thanks to both members for your help regarding wire and tuner mtg supports. regards--Johngeorgetownjohn — 09:33 AM
Hickok AC51 tube tester
Note that no power cord, power switch, or power transformer switch are shown. That (along with my experience with full s...DaleHCook — 07:09 AM
IF can wire size and Rubber mounts?
A pair of wire strippers can give you an idea of what the existing gauge of the wire leads are in the IF can, I think it...Arran — 06:07 AM
My last cabinet for this year
Hello Dan, That is really beautiful what great looking radio you have ! I have friends who live in Calgary and the wea...radiorich — 01:51 AM
Philco Predicta Siesta picture over time getting dimmer
I found that the wire insulation was burnt.  The fly back needs corona dope! Why would someone put that there?Platinumblonde36 — 01:09 AM
Philco Predicta Siesta picture over time getting dimmer
This is what it looked like beforePlatinumblonde36 — 01:01 AM
Philco Predicta Siesta picture over time getting dimmer
Platinumblonde36 — 12:58 AM

[-]
Who's Online
There are currently 5043 online users. [Complete List]
» 1 Member(s) | 5042 Guest(s)
Avatar

>