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

40-190 What is this?
#5

I would suggest that you disconnect the added toilet paper roll antenna and then disconnect each lead of the original rotating loop antenna below and check for open circuits in one coil winding. The antenna coil can be repaired but you would have to unfasten the electrostatic outer shield covering to get at the coils inside. Most likely a wire has corroded apart at one of the fastening points inside. I repaired and restored a 40-201 and worked on the one in it. This electrostatically shielded antenna loop was only used in 1940 models. It helps eliminate noise interference from neon lights and motors that may have a spark jumping inside them. The antenna circuit of the 1940 models with this feature have a high impedance RF amplifier grid circuit. 1941 models changed to a low impedance loop and grid circuit in the RF amplifier stage to reduce noise.

Joe


Messages In This Thread
40-190 What is this? - by Edisla - 07-19-2015, 12:47 PM
RE: 40-190 What is this? - by morzh - 07-19-2015, 03:44 PM
RE: 40-190 What is this? - by Arran - 07-19-2015, 05:00 PM
RE: 40-190 What is this? - by DeckApe - 07-20-2015, 10:43 PM
RE: 40-190 What is this? - by Joeztech - 08-01-2015, 03:41 PM
RE: 40-190 What is this? - by Edisla - 08-02-2015, 01:01 PM
RE: 40-190 What is this? - by Edisla - 08-02-2015, 01:03 PM
RE: 40-190 What is this? - by DeckApe - 08-16-2015, 10:10 PM
RE: 40-190 What is this? - by Edisla - 10-07-2015, 09:36 PM
RE: 40-190 What is this? - by Edisla - 10-07-2015, 09:37 PM
RE: 40-190 What is this? - by Ron Ramirez - 10-07-2015, 09:43 PM



Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
6TPZ and 5TPO Radio Help
OK, so 18 and 19 as they should be. What is "everything else?" Try to be more specific in your descriptions:...morzh — 12:44 PM
6TPZ and 5TPO Radio Help
Yeah, I'm still on 5TPO. Sorry, my bad, points 1 and 2 should be points 18 and 19 (easy mistake  :think: )  X7 is shown ...R3Sons — 11:42 AM
Philco 40-120C Filament Wiring
Hi folks, I'm in the process of restoring a Philco 40-120C and I'm finding the wiring to be a bit puzzling. According to...bluecap — 11:28 AM
462ron
Hi Levi, here’s just a thought. Most radios run the oscillator higher than the dial setting. Say you set your radio to 1...462ron — 10:10 AM
1930s Stewart-Warner Tombstone Radio need help identifying model number
Another Update: I found a couple of damaged coils inside this radio that might have something to do with why this radio ...captainclock1988 — 10:51 PM
6TPZ and 5TPO Radio Help
If you are still on 5TPO, you lost me there. What X7? What Points 1 and 2?morzh — 08:37 PM
6TPZ and 5TPO Radio Help
Quick progress report: X7 is broken. Only one leg soldered, the other missing and the diode is cracked. I've replaced...R3Sons — 05:05 PM
6TPZ and 5TPO Radio Help
Oh...and you have electrolytic caps there. All need to go and be replaced.morzh — 04:36 PM
6TPZ and 5TPO Radio Help
Thanks, will do.R3Sons — 01:25 PM
1930s Stewart-Warner Tombstone Radio need help identifying model number
UPDATE: I was able to pick up a signal generator on the cheap (amazingly enough) on feebay and I did an IF alignment fol...captainclock1988 — 09:53 AM

[-]
Who's Online
There are currently 6139 online users. [Complete List]
» 2 Member(s) | 6137 Guest(s)
AvatarAvatar

>