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

Power transformer in a 12 volt/25 volt radio?
#11

Sorry, I have old man eyes. How about this one? A 166J25:

http://www.digikey.com/product-detail/en...-ND/270154

There is a 166M25 version with a 3 amp rating which would be more what I need, right? In this radio, the chassis is fairly small and squarish. Inside the cabinet, there is tons of open space.

It would be more elegant (I guess that is the right word) to swap all of the tubes for their 6 volt varieties and change the output to a 6V6, but I know for a fact that my grip on theory isn't up to it. My tube manual says that the 6 volt versions of all of the 12 volt tubes are electronically identical, so (except for changing the heater voltage) I would not need to make any changes there, I suppose. It is changing the 25L6GT to a 6V6GT that worries me. The value of the resistor between the plate of the 12SQ7 and the 25L6GT is 100 ohms, so that needs to be more like 300 if I change it to a 6V6, right? I do actually have an output transformer and speaker matched to a 6V6 around here that came out of a Crosley 66Cs but the cone is a bit rough...I wonder if I could canabalize the OT and match it to the Stewart Warner FC and speaker? Probably not. But the changes to R13, 10, and C 27, C 28, C38, and C 59 A and B?  Plus anything else I'm missing from ignorance? It would be a great education for me, and force me to finally get better at calculating resistances and impedances.  

Like I said, I kind of love the cabinet, and the phono input is a plus, so I'd like to get the set working one day.

Charlie in San Antonio


Messages In This Thread
RE: Power transformer in a 12 volt/25 volt radio? - by ccomer1955 - 11-28-2016, 12:42 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
An attempt to remove the Field Coil from a G speaker
Hi Morzh, May be a good idea to remove the cone to prevent damage. You may have to do so anyway to remove the pole ...MrFixr55 — 08:44 PM
Philco 91 Restore Code ??
I think that Danaher, the company that owns Beckman-Coulter (the company that I worked for 41 years) owns Fluke. They a...MrFixr55 — 08:35 PM
Philco 91 Restore Code ??
Rod I wish... :lol: I am not sure I'd buy the Fluke, had it not fell in my lap for free. $500 to $800...it's a lot...morzh — 08:09 PM
Philco 91 Restore Code ??
Mike, ...you get a commission?RodB — 07:52 PM
New member
Hi. I specialize in refurbishing Predictas, but I'm in Chicago. If you can get it to me, I'd be happy to go over it. ...Bob Andersen — 06:43 PM
An attempt to remove the Field Coil from a G speaker
I have 3 G speaker, all with open Field coils. Today I pull one of the shelf and decided to try to remove the FC (spo...morzh — 06:07 PM
Philco 91 Restore Code ??
Thanks Mike. I will check them out.dconant — 05:52 PM
Philco 91 Restore Code ??
There is no such thing as bad Fluke. This said, they are expensive. A Fluke is easily 10x the price of comparable CCC...morzh — 05:45 PM
Philco 91 Restore Code ??
Hello Mike, Yes, I have 3 Fluke meters one being my first Fluke 77 and other being Fluke 87. My third is Fluke clamp -...radiorich — 05:04 PM
Philco 91 Restore Code ??
I knew that Fluke was the Cadillac so with that in mind what Fluke would you recommend I get?dconant — 03:53 PM

[-]
Who's Online
There are currently 4443 online users. [Complete List]
» 1 Member(s) | 4442 Guest(s)
Avatar

>