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

Philco 76 output transformer #2848
#16

That's sort of an odd design for an output transformer, most of the ones I have seen have the secondary on the outside, not the primary.
Regards
Arran
#17

I tried my best to exact a copy of the original. I dont know that I want to do another. And I have yet to see it in action, so..

Stan
#18

Well I finally got my output transformer stitched up, and back on the speaker. To my surprise it works. I have yet to do the voltage checks, and I'm not real happy with some of the things I had to do in the end. This was my first, maybe the next will come out better. The big thing is, I did it, and it worked!
#19

Well, The radio seems to play ok, but voltage checks have me scratching my head. The voltages all seem to be a bit high(DMM), but I have more than double the listed plate voltage on the Detector tube, and the first AF tube. By the resistance chart things are almost spot on, and PT voltages are good. Tubes good. My new field coil, by the DC resistance is 3245ohm. My rewound OPT is the only thing I can think of that may not be exactly like it should be.
#20

The plot thickens how about the voltage on the 24A's plates? There are fed off of the same line.

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
#21

Keep in mind, these were taken with a DMM.

Stan


Attached Files Image(s)
   
#22

Would check #14 100k resistor. If drifted lower in value this will raise the voltage. Poor ground at #14. Weak 24A. Clean heater contacts on socket & tube (24A det). Just for grins you can try grounding the control grid (grid cap) and check the plate voltage. If the voltage drops to a more normal level you may have a open 2ndry on the rf coil or bad ground.

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
#23
Wink 

Thank you for that Terry. You have given me some things to look at. I am now unstumped, for now.Icon_smile

Stan




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
The list of my radio & TV collection!
A little light Saturday positive about our hobby in our feed... My new every Saturday video about antique radio equipme...RadioSvit — 02:12 PM
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. But I can't find those articles.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

[-]
Who's Online
There are currently 700 online users. [Complete List]
» 1 Member(s) | 699 Guest(s)
Avatar

>