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

Replacing 1st and 2nd IF transformers
#1

Want to replace the small IF transformers on a GE model 401 with the larger capacitive tuned transformers.  This chassis has the holes for the larger transformers mounting studs although it looks like either transformer could be used. GE used both the small inductiveley tuned transformers as well as the larger capacitively tuned transformers on the models 400, 401, and 411 although the schematic shows the larger transformers.  Maybe they used the smaller ones in later sets? Later models like the 412 and 416 used the smaller transformers,  but the chassis and components were about the same. On the schematic with the large transformers,  it shows a DC resistance on the windings of 24 ohms. I have obtained a set of transformers off of ebay that all measure 13.8 ohms. Was wondering if it would cause a problem if I use these transformers with a different DC resistance value? Any thoughts or ideas? Thanks!!!
#2

Size and resistance doesn't matter so much what does is the resonant frequency. If it's 455kc your good. But if they are the small Ktran style transformer they are prone to develop smd. The input and output transformers are somewhat different impedance wise is it's good to determine which is which.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Model 70 Cabinet Trim
musar , Well if you have any more questions feel free to post away . Sincerely Richardradiorich — 08:56 PM
Model 70 Cabinet Trim
Although I have not made any cabinets or cabinet parts for a couple of years, I still have some parts left over, includi...Steve Davis — 06:26 PM
philcorepairbench.com - shadow-meter
Thanks Ron.fenbach — 02:43 PM
Model 70 Cabinet Trim
Thank you, Gary. Before making my original post, I had clicked on "Steve Davis Cabinets" only to find that it...musar — 02:25 PM
philco predicta
Welcome to the Phorum, cgl18! I am not your resource for television repair, but lots of friendly help is available here...GarySP — 02:12 PM
Model 70 Cabinet Trim
Welcome to the Phorum, musar! You can send Steve Davis a private message (PM). The site is at the top of the Home page...GarySP — 02:09 PM
Model 70 Cabinet Trim
How do I contact him? The only contact information for him I could find when searching online was a telephone number th...musar — 10:38 AM
philco predicta
Hello, good afternoon, I would like to ask what the possible problem could be if I don't have an image on the screen. I ...cgl18 — 10:19 AM
Philco model 38 code 121 not receiving signal.
So one last question before I finish this radio. Regarding the speaker and output transformer. I salvaged the original o...Stormlord5500 — 09:31 AM
462ron
It’s on the bottom of the homepage of our Philcoradio.com homepage! Ron462ron — 07:20 AM

[-]
Who's Online
There are currently 542 online users. [Complete List]
» 3 Member(s) | 539 Guest(s)
AvatarAvatarAvatar

>