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
Philco model #20
AHH HA , I got it and can’t thank you fellows enough , when I changed the capacitors I took the advice and did not unsol...onlyrick — 02:24 PM
Zenith H725
Hello Ed, yes, I like letting projects run for few days to make sure they don't start acting up . Sincerely Richardradiorich — 01:03 PM
Philco 46-480 Electronic Restoration
I am almost finished with this restoration. All which remains is the power transformer. I cleaned it up some time ago, b...jrblasde — 12:41 PM
Philco model #20
I seem to recall in some TRF sets there being a Local/Distance toggle switch that removes the B+ from the first 24 rf tu...RodB — 09:46 AM
Refinishing Ideas
Hi Doppelganger, After rereading your thread, did you mount the Zenith speakers in the two bottom left and right pos...MrFixr55 — 09:39 AM
Philco model #20
Hi Rick, One other thing regarding volume on this set.  Make sure that the tube shield is in place.  this is that la...MrFixr55 — 08:22 AM
Philco model #20
Hi Rick, The volume control on the Model 20 has 2 sections and does 2 seperate things: One part of the control, ...MrFixr55 — 10:30 PM
Philco model #20
Hello again fellows , well I powered up the set this evening after I had changed every cap and resistor in this set and ...onlyrick — 09:34 PM
Zenith H725
Yes - better it happened on the repair bench than returning to the owner. The other question is - do I also dissect a...EdHolland — 09:08 PM
Zenith H725
That's a bummer but get them now. Paul BPaul Philco322 — 08:27 PM

[-]
Who's Online
There are currently 793 online users. [Complete List]
» 1 Member(s) | 792 Guest(s)
Avatar

>