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

41-250 Antenna circuit wiring
#1

I'm trying to trouble shot a problem in the front end of my Model 41-250 and am finding that the schematic and actual wiring don't seem to agree. The radio works well on the two broadcast and highest shortwave band but has a hum on all signals in the 2.5 to 7 Mc band. I suspect maybe an open ground when the bandswitch is in that position. Since the radio works well on three of the four bands, I can't figure out why I can not get the schematic and actual wiring to match up. I've been in electronics for over 50 years and once in a while you come up with a strange situation like this. Any suggestions.

Harv
#2

Hello Harv. If the set has been previously "hacked", perhaps there is a missing bypass cap previously removed and not replaced? You mentioned the schemat doesnt match. Ive had luck in the past locating orig missing caps by taking a .05/600v , clip a wire with alligator clips to ground one end of the cap to chassis. Then by probing around with the other end of the capacitor lead-wire "point to point" on different connections one at a time can find missing bypass locations and rid hum. Just remember to discharge the cap "probing lead" back to chassis before touching it to all your different test points one test at a time! Icon_wink
#3

Can you take photos of your chassis? if so, I will compare it to mine.

I completely rewired mine, and it worked the first time! I do not yet have a working analog volt meter and RF signal generator, so have not yet aligned it.

Web site: http://www.masekconsulting.net
Radio Photos: http://www.photobucket.com - album id FStephenMasek
#4

Thanks for your offer, but I have solved my problem and the radio is working. My issue was with the way the antenna coil was wired, but since the radio works OK I guess it was just the way I was looking at things. Thanks again.

Harv




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
trying to identify this wire type
It's possible that the red wire, actually a grid cap lead, is a very old replacement, I can't remember seeing a pre 1939...Arran — 09:18 PM
Gilfillan Brothers Car Radio?
Hi everyone,  Special thanks to Joe Rossi for tracking down this obscure radio and thanks to others who took up the hun...Antipodal — 08:15 PM
trying to identify this wire type
Here's one source for your wire of many. Take care and BE HEALTHY! Gary P.S. Can't get the right color you need? I ...GarySP — 06:40 PM
trying to identify this wire type
...and modern wire of the appropriate gauges and insulation V-rating (300V minimum, usually shown right on the wire) is ...morzh — 05:47 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
I have a question about this radio, is there anyone that has access to this radio that has an intact unmolested speaker ...captainclock1988 — 04:28 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
Well what makes me confuse all of those companies is that all three of those companies (Setchell-Carlson, Stromberg-Carl...captainclock1988 — 04:21 PM
trying to identify this wire type
The red wire is rubber covered wire. The others are cotton braid over rubber often in colors or a tracer, also strand...Chas — 02:43 PM
trying to identify this wire type
Greetings Phorum members, Hope you can help me identify this type of wire in the photo I have attached.  I am not sure ...georgetownjohn — 01:53 PM
Philco 60 Squealing
All correct shields must be in place, all tubes correct no subs of any kind. Check any soldered, riveted ground conne...Chas — 01:24 PM
Philco 60 Squealing
I have recapped and replaced out of tolerance resistors and so on. Radio plays nicely on fairly strong stations. The pro...dconant — 10:55 AM

[-]
Who's Online
There are currently 3358 online users. [Complete List]
» 2 Member(s) | 3356 Guest(s)
AvatarAvatar

>