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

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

Model 90 Stuck At One Volume Level
#9

So I've gone over the complete schematic (for the 3rd time now) and highlighted every circuit. I find nothing that's out of place, open, shorted etc. I still have about 50% volume with no control over it. I checked the AVC at the junction of #46 & #48 reading to chassis ground and I do see a substantial change in the negative voltage at this point when I go on and off of station.

I ground the grid of the Det. Amp. and I still have the same volume. I remove the Det. Amp. tube and my volume goes away completely. This is about all I can tell you. I'M STUMPED!

EDIT: There is one thing that I have in question. The #55 choke. It is obviously an aftermarket product. I read about 150 ohms across it's leads. I have no reference on this so I don't even know if it matters.

Pepper

"It's Nice To Be Nice To The Nice"
Major Frank Burns Mash 4077th


Messages In This Thread
Model 90 Stuck At One Volume Level - by Pepperoni - 04-12-2012, 04:54 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-12-2012, 10:19 PM
RE: Model 90 Stuck At One Volume Level - by Pepperoni - 04-13-2012, 04:39 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-14-2012, 03:44 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-14-2012, 03:52 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-14-2012, 07:16 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-14-2012, 09:51 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-15-2012, 01:04 PM
RE: Model 90 Stuck At One Volume Level - by morzh - 04-15-2012, 02:26 PM



Users browsing this thread: 8 Guest(s)
[-]
Recent Posts
Philco model 60
>>and found that the field coil is bad. Should be 1140 ohms, tests at 1.1k ohms. You have one stringent crit...morzh — 02:07 PM
Philco model 60
Yes I was there. I got some real bargains there. Plus a Zenith 7G605 clipper that I have been trying to find for a fair ...Radios1340 — 01:46 PM
The speaker table error?
G  10-1/2"       65, 76, 87, 95 Push-Pull 45's 2766 0.7 550 3200 H   10-1/2"    77, 96 Push-Pull...morzh — 09:26 PM
A Marconi model 86
I have a Stromberg, one of the early ones, seems early 30s. This is what I call a back breaker. None of the early Philc...morzh — 08:28 PM
A Marconi model 86
A backbreaker.....PaulPaul Philco322 — 08:12 PM
A Marconi model 86
>>What a behemoth! A Juggernaut.morzh — 07:47 PM
Philco 70 antenna lead
I am not sure I understood about the coils and the mush. I looked an more than one coil in 20, 70, 90, 60, Zeniths and ...morzh — 07:46 PM
A Marconi model 86
:e_biggrin: What a behemoth!  I hope the final result is as much a quality sounding example!  Keep us posted on your pro...GarySP — 07:32 PM
A Marconi model 86
I should add that the double conversion may only be used on the shortwave bands, but I haven't looked at the schematic t...Arran — 07:27 PM
Philco 70 antenna lead
Yes, that wire will not pick up much interference as routed - the RF at that level won't be affected, and if you have st...radio1 — 07:26 PM

[-]
Who's Online
There are currently 7782 online users. [Complete List]
» 2 Member(s) | 7780 Guest(s)
AvatarAvatar

>