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-   -   Need help with my 16" round tube Admiral tv (http://www.videokarma.org/showthread.php?t=261891)

Bill Cahill 06-17-2014 06:20 PM

Need help with my 16" round tube Admiral tv
 
First, I lost the schematic. It's a straight tv only. Console with half doors. Don't remember model number. Secondly, can somebody help me with a good correct replacement power transformer for it? Either new, or on a chassis??
Please help, guys. Thanks.
Bill Cahill

Uses single 5U4 rectifier tube on chassis. Power transformer is completely under chassis.

Bill Cahill 09-01-2014 02:09 PM

Finally, I found the Chassis number to the set. It is 21D1. I desperately need the power transformer for this set, and, schematic. The rectangular version isn't very close. Can somebody please help me?? Maybe you have a chassis with a good transformer?? Or, can someone find me a new old stock replacement?
Thank You..
Bill Cahill

nasadowsk 09-01-2014 06:43 PM

Got a part # on the xfmr?

Bill Cahill 09-02-2014 07:26 AM

Actually, I have several part numbers. Here they are.........

Merit P 2867

Stancor P 8164

Triad R 66F35

Hope you can help. Thanks.
Bill Cahill

Findm-Keepm 09-02-2014 07:36 AM

Play Things of the Past lists two Admiral TV power transformers - you didn't give the original number (which would help!), but the two they list are:

80B58-1 and 80C26-2

Also, what are the secondary windings? Sometimes a tranny with an additional winding will work, you just don't need/use the additional winding.
Or, one without the rectifier filament winding will do if you convert to a silicon diode.

I've got Triad, Thordarson, and Merit Transformers, but need more info to see if any of mine might even be close.

Cheers,

Bill Cahill 09-02-2014 07:59 AM

The part numbers I gave are exact replacements. John didn't give me the Admiral part number.
No, I don't wish to go to silicon rectifiers.

earlyfilm 09-02-2014 09:37 AM

Quote:

Originally Posted by Bill Cahill (Post 3114050)
. . . . 21D1. . . . I desperately need the power transformer for this set, and, schematic.

The schematic is the last schematic in the 26 page 21D1 Rider manual:

http://www.earlytelevision.org/tv_sc...s_postwar.html

Jas.

Findm-Keepm 09-02-2014 01:15 PM

Working backwards, both Admiral part number 80C26-1 crosses to the Merit P 2867.

Thordarson lists the original transformer number for the 21D1 as 80C26-1, and crosses it to a Thordarson 26R71. The 80C26-2 carried by Play Things of the Past also crosses to the 26R71. The 80C26-2 is listed as used used in the 20V1 and 20T1 chassis.

I have neither, and can't go any further.


Cheers,

Bill Cahill 09-02-2014 01:37 PM

According to what I can find out, the Thordarson transformer is for a set that used a 5V4 damper. My Admiral uses a 6W4 with an isolated hv winding for the filament, due to cathode being tied to it like RCA did.
Who was the big internet company that carried new old stock tv transformers?
I was told to call Mark Oprat. I did. He was friendly, but, doubted he'd have one, and, said he couldn't look for 3-4 weeks. He said to talk to Gary at play things of the past, and, he didn't even want to take the time to look up part numbers. He said I must have all the factory data, including exact sizes, ratings, etc....
Not having much luck here...Hasn't anyone got a spare set they could part out??

Findm-Keepm 09-02-2014 01:58 PM

All of the transformers you have listed and the Thordarson have 3 secondary windings - B+, 6.3V and 5V. No difference between them that I can see.

Look at the schematic on ARF (page 26 of 26) - the damper filament is fed by the power transformer.

Cheers,

old_coot88 09-02-2014 02:18 PM

Why not use a stand-alone 6.3V xfmr for the damper heater?

Bill Cahill 09-02-2014 02:25 PM

I had two new old stock stand alones, and, they were both shorted.
They have to be rated at 2KV insulation due to the pulse.
I know the damper gets it's filament power from the transformer. It's a separate 6volt winding rated for hv insulation....
Called Moyer electronics. They are going to call me back on availability.....
I'm also looking for a power transformer for my RCA 8TR29. It works, but, due to past severe dampness, has a lot of leakage from primary to chassis.
See my post on it in my forums. I actually had the set playing last year...

bandersen 09-02-2014 03:48 PM

According to the schematic, the 6W4 damper tube filament is in parallel with all the other tubes - no separate filament winding :scratch2:

Kevin Kuehn 09-02-2014 04:01 PM

So apparently Bill's is not really a 21D1 chassis? Seems like that chassis number should be stamped on the back side of his chassis.

old_coot88 09-02-2014 04:51 PM

After jogging the old memory cells, i don't recall ever seeing damper tubes such as 6W4, 6AX4 etc. using a dedicated heater winding. They had adequate H-K breakdown rating and ran the heater off the common 6.3V winding.
(6W4 does not have the heater tied to the cathode. )


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