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

GM model 120A ser. 7247A (power resistor)
#1

Hello, I have recently acquired a GM model 120A "The Hepplewhite". Did some cleaning and replacing bypass caps in the metal cans and checking the power resistor/voltage divider found it has an open in the 1st, 3rd and 4th resistors, see the attached photos. Does any one know the values of these resistors?
In the drawing of the voltage divider the 2nd is 60 ohm and the 5th is 450 ohm. One might guess by looking at the spacing of the tabs that the narrow spaced tabs would be the lower values and as the spacing gets wider the resistance would be higher, just a thought. If anyone has some suggestions for the open resistor values it would be greatly appreciated, I only have a couple 10W resistors to work with. I would like to purchase a variety of resistors to keep and at least come close to the values needed to fix this radio.
Thanks, Steve    


Attached Files Image(s)
       
#2

Unable to answer your question the only info I could find was from Beitmans and a link to Nostalgia air. Sorry I could not be of more help. David     http://www.nostalgiaair.org/Resources/915/M0039915.htm    
#3

Hello Steve,
That is very funny Because I know of another guy including myself who has a radio with this chassis ,
My General motors model 160 that  is called the Georgian Style .
The values of that resistor is different among some the models  anyway my resistor was also open but one the other members gave me these values .

Sincerely Richard


Attached Files Image(s)
   
#4

Hello Steve,
hopefully that helps you anyway mine came with a turntable too .
I still need to get my speaker fixed .

Sincerely Richard
#5

Hi Richard,
Thanks for the quick response, those values give me a place to start. I'm going to guess the ground connection is between the 4.8k and 59. I really like the looks of the Gregorian that you have mine is so plain looking in comparison but glad to own it non the less.
Excited to get it working again, will try to post updates.

Thanks again, Steve
#6

Hello Steve,
Craziest thig was there was another model for sale like a year after i bought mine in the same small town
yes that is where the ground is .

Can't wait to see more on your far as update and progress !

Sincerely Richard




Users browsing this thread:
[-]
Recent Posts
Zenith H725
I just remembered, I have some hi temp silicone rubber material which could do the trick. Or a piece of FR4 laminate. Th...EdHolland — 08:39 PM
Zenith H725
The PSU filter cap arrived today (thank you USPS!) so I will work on that later. Meanwhile, I have the dial, speaker...EdHolland — 06:42 PM
Philco 610B oscillator wiring
Thanks Terry. After checking my notes I think I recorded about -10v at the 6A7 G4/control grid. The screen grid (G3 &...Tubester — 05:59 PM
The list of my radio & TV collection!
Magical chords of forgotten melodies, old nostalgic music on an old radio... Saturday night blues on the Mid-Waves on an...RadioSvit — 12:20 PM
Philco 42-345 Restoration/Repair
Thank you MrFixr55 the issue with this radio is that the internal coil antenna is missing and there was a wire in its pl...osanders0311 — 11:34 AM
Philco 610B oscillator wiring
Regarding the oscillator circuit which is comprised of the 6A7's cathode, control grid, and screen grid. These elements ...Radioroslyn — 10:33 AM
Philco 42-345 Restoration/Repair
Hi OSanders, First off, welcome to the Philco Phorum where Phine Phamily-Phriendly Pholks Phull of Philco Phacts and P...MrFixr55 — 08:41 AM
Philco 42-345 Restoration/Repair
Today I've been reading through the site trying to learn more about this radio. I also soldered the lose power cord cabl...osanders0311 — 08:24 PM
Philco 610B oscillator wiring
Thanks David! I do have that same later prodution model 610 schematic. I've also studied the Philco service bulletins fo...Tubester — 08:12 PM
Philco 610B oscillator wiring
Some info from Beitmans says late production. David   David — 06:06 PM

[-]
Who's Online
There are currently 1921 online users. [Complete List]
» 2 Member(s) | 1919 Guest(s)
AvatarAvatar

>