Videokarma.org

Go Back   Videokarma.org TV - Video - Vintage Television & Radio Forums > Antique Radio

We appreciate your help

in keeping this site going.
Reply
 
Thread Tools Display Modes
  #1  
Old 08-12-2015, 09:36 PM
Winky Dink's Avatar
Winky Dink Winky Dink is offline
VideoKarma Member
 
Join Date: Apr 2010
Location: Meridian, Idaho.
Posts: 583
New Project: GE F-80

I’m restoring a GE Model F-80 radio (c1938) which has had a lot of repairs done--perhaps shortly post-war as parts became available ( “10/31/46 is penciled on the chassis). I need advice on one of the IF transformers.

Here’s what the third IF transformer looks like. I’m guessing that the burned dog bone resistor is a replacement part, but the schematic also shows a second mica capacitor.



Below (left) is the original schematic with my re-drawing of the current status (right).



So, should I restore to the original specs--replacing the dog bone and adding the missing C-28? If I add the missing C-28 I’ll replace C-27 as well, but what should I use as replacements. I have available 500V silver-micas, 630V polystyrenes, and 1KV-6KV ceramic disks.

Thanks (but be warned that I’ll be asking about the dreaded Candohm resistor at some future time).
__________________
Winky Dink
Damn the patina,
Full speed ahead!
Reply With Quote
  #2  
Old 08-15-2015, 03:29 AM
Winky Dink's Avatar
Winky Dink Winky Dink is offline
VideoKarma Member
 
Join Date: Apr 2010
Location: Meridian, Idaho.
Posts: 583
Brilliant Move?

(Replying to my own post... Is this a sign of early dementia?)

I decided to use the configuration on the schematic and replace the 250pF mica cap which tested about 300pF, so I fabricated two new 250pF caps using 100pF and 250pF 500V polystyrene caps.



Intuitively I avoided placing the components between the coils. This little job took me a full three hours, but that included the time it took to fix the coil connection that I broke and to replace the terminal that I broke on the underchassis side of the transformer.

__________________
Winky Dink
Damn the patina,
Full speed ahead!
Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 04:21 PM.



Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
©Copyright 2012 VideoKarma.org, All rights reserved.