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

Rolla field coil speaker?
#1

Let me apologize in advance since this post has nothing to do with Philco radios or any vintage raadio.

I'm restoring a Gibson GA 6 F guitar amp with a Rolla field coil speaker. The speaker has the usual field coil winding and another winding that is connected in series with the speaker voice coil and secondary of the output transformer. Can someone tell me what the purpose of this winding is?

Any information would be greatly appreciated.
#2

Sorry, the model number of the amp I'm working on is BR-6F .
#3

Sounds like the "hum bucking" winding used on most radios of the 1930s. It was phased with the voice coil winding to remove any residual hum caused by the field winding.

Harv




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Cannot Adjust an IF Transformer’s cores
Outstanding work indeed. I wish I could come up with solutions like this.slford310 — 11:16 PM
Cannot Adjust an IF Transformer’s cores
The abilities of our 'Phorum Pholks" never ceases to amaze me! Fantastic fabrication, Joseph! I'm waiting now for...GarySP — 08:27 PM
PT-6 antenna connections
Thanks. I never realized that was a notch noted in the schematic as described. I’ll recheck my wiring.bridkarl — 08:13 PM
Cannot Adjust an IF Transformer’s cores
Thank you! I was quite new to the Phorum when I started this post, so I feel like it might be advantageous to publish a ...jrblasde — 08:07 PM
PT-6 antenna connections
Notice in the schematic the notch at the bottom of the antenna coil is between pins 3 & 4. Yes, pin 6 of the 7C6 is...RodB — 07:34 PM
bridkarl
I have two PT-6 chassis. On both there is a blue wire that runs from the above chassis transformer to pin 6 of 7C6. So t...bridkarl — 07:23 PM
Cannot Adjust an IF Transformer’s cores
Joseph, now you are an engineer!!RodB — 06:37 PM
PT-6 antenna connections
Hi, reading your explanation I can see the confusion. If you take it one connection at a time it should result in a desi...RodB — 06:34 PM
Cannot Adjust an IF Transformer’s cores
It works! I received the PCBs this morning in the mail, and put everything together. I reused the base from the original...jrblasde — 04:32 PM
PT-6 antenna connections
I seem to have lost my way on this PT-6. I see the antenna aerial transformer schematic - I’m reading pins 1 through ...bridkarl — 12:30 PM

[-]
Who's Online
There are currently no members online.

>