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-   -   Mystery chassis....?? (http://www.videokarma.org/showthread.php?t=267031)

Kamakiri 05-19-2016 02:30 PM

Mystery chassis....??
 
4 Attachment(s)
Got this chassis as a present from DavGoodlin :)

He said it was an Admiral, but there's no way it's an Admiral. Take a gander and see what you think it is......

The only indication is a mark of Emerson on the ballast tube, but I can't find any Emerson sets that have this style control layout.

Look at all the filter cans!!! :eek: And a ballast tube and selenium rectifiers with a 12" screen. This is an odd duck, whatever it is.....

jr_tech 05-19-2016 02:40 PM

Emerson for sure...In the earlier 10" model the 5 holes at the rear of the chassis were populated with 25Z6 rectifiers.

jr

rca2000 05-19-2016 02:42 PM

Pretty sure it is an EMERSON chassis Tim. Had one like it 35+ years ago. Pretty sure it is HOT--that tranny is only for filaments..

jr_tech 05-19-2016 03:00 PM

I have never seen the 12" model but this chassis likely came out of a combo like the 618 or 630.

http://ebid.s3.amazonaws.com/upload_...7-16520-24.jpg

edit add: earlier thread about a 10" model found in Denver:

http://www.videokarma.org/showthread.php?t=266947

jr

Eric H 05-19-2016 03:32 PM

Could be an Emerson 571B, the 571A had the 25Z6 nightmare, the 571B had Seleniums IIRC.
Definitely Emerson though.

In any case it's an awful set to recap, just look at all those cans!

Edit, you said it has a 12" tube so not a 571.

http://www.vintagetvsets.com/images/emerson571.jpg

Kamakiri 05-19-2016 05:25 PM

Well, either way.....it's getting stripped and hitting the curb unless someone needs parts off'n it. Testing the 12LP4, so we'll hope for the best there :)

stromberg6 05-19-2016 06:56 PM

I recently "did" an Emerson 698 14 inch from 1951, and it was a real PIA. One of the only things that saved it from being parted out was that the 14BP4 has excellent emission, and also it is a very clean set, inside and out. And it's small. The power supply circuitry is a nightmare, and I wonder about the EE's who designed it. Still has some fold over issues, but I'm done with it for now. Decent pic though, aside from the minor deflection issue. :yes:
Kevin

kramden66 05-19-2016 07:11 PM

Emerson for sure I have a double d 10" that looks like that

rca2000 05-19-2016 07:21 PM

I wondered back in 1980 or so...ans STILL do wonder today--seeing that picture again..why did they use SO MANY filter cans? Reminds me of the "locomotive chassis" that has a lot of caps --I think the 1st gen or so.. I understand the ened for a few caps for a doubler and filtering--but beyond that?

jr_tech 05-19-2016 07:55 PM

Quote:

Originally Posted by rca2000 (Post 3162964)
I wondered back in 1980 or so...ans STILL do wonder today--seeing that picture again..why did they use SO MANY filter cans? Reminds me of the "locomotive chassis" that has a lot of caps --I think the 1st gen or so.. I understand the ened for a few caps for a doubler and filtering--but beyond that?

This Sams from the ETF site reveals that the set had *two* well filtered voltage doubler supplies, one positive and the other negative. Both the 25Z6 and selenium versions are shown..... lots of caps!

http://www.earlytelevision.org/pdf/E...Sams-76-11.pdf

jr

Jeffhs 05-19-2016 08:34 PM

Quote:

Originally Posted by Kamakiri (Post 3162941)
Got this chassis as a present from DavGoodlin :)

He said it was an Admiral, but there's no way it's an Admiral. Take a gander and see what you think it is......

The only indication is a mark of Emerson on the ballast tube, but I can't find any Emerson sets that have this style control layout.

Look at all the filter cans!!! :eek: And a ballast tube and selenium rectifiers with a 12" screen. This is an odd duck, whatever it is.....

It probably is an Emerson set. I saw at least two Emerson branded tubes in the chassis.

I don't know where you saw that Emerson logo. I looked at the ballast tube and didn't see anything but a perforated cylinder over the tube itself; there was no logo on that cylinder, unless I was looking at the wrong part.

BTW, this is the first TV I've ever seen that uses a ballast tube in the power supply. Every set I've ever worked on has had a power transformer and at least one 5U4 rectifier, or series string filaments with seleniums.

That this set uses a ballast tube probably dates it to the late 1940s--'47 or '48. By 1950, however, I am sure the 5U4 had taken hold as the rectifier tube of choice in most TVs, although my folks' second set, a 1955 Crosley Super V 21" b&w console, still used selenium B+ rectifiers. That set had two such rectifiers, probably wired in parallel across the output of the B+ supply. The plate voltage for the tubes was probably taken directly from the output of the rectifiers and fed through at least one filter capacitor.

rca2000 05-19-2016 09:35 PM

Transformer is only for filaments.. set is HOT.. pair of doublers for B+ and B-

jr_tech 05-19-2016 09:57 PM

Quote:

Originally Posted by rca2000 (Post 3162978)
Transformer is only for filaments.. set is HOT.. pair of doublers for B+ and B-

Did you catch the error(s) on the 25Z6 supply in the Sams that I linked?

jr

dieseljeep 05-19-2016 10:00 PM

Quote:

Originally Posted by Jeffhs (Post 3162976)
It probably is an Emerson set. I saw at least two Emerson branded tubes in the chassis.

I don't know where you saw that Emerson logo. I looked at the ballast tube and didn't see anything but a perforated cylinder over the tube itself; there was no logo on that cylinder, unless I was looking at the wrong part.

BTW, this is the first TV I've ever seen that uses a ballast tube in the power supply. Every set I've ever worked on has had a power transformer and at least one 5U4 rectifier, or series string filaments with seleniums.

That this set uses a ballast tube probably dates it to the late 1940s--'47 or '48. By 1950, however, I am sure the 5U4 had taken hold as the rectifier tube of choice in most TVs, although my folks' second set, a 1955 Crosley Super V 21" b&w console, still used selenium B+ rectifiers. That set had two such rectifiers, probably wired in parallel across the output of the B+ supply. The plate voltage for the tubes was probably taken directly from the output of the rectifiers and fed through at least one filter capacitor.

The set, definately is an Emerson 1949, 12" chassis from a TV, radio, phono combination.
The first set, my parents bought was the TV only model, using that type chassis. A smaller type console, where the speaker was as large as the picture. The ballast was for surge limiting of the two power supplies.
The CRT went weak, when the set was about four years old. They gave it to me, to take it apart when I was about ten years old.
Regarding the Crosley set, that model used a voltage doubler, two seleniums and a voltage doubling cap, before the two rectifiers and two caps and a choke to furnish the B+ voltages. It also used the audio output tube as a voltage divider. I common scheme that many manufacturers used. :thmbsp:

rca2000 05-19-2016 10:21 PM

Quote:

Originally Posted by jr_tech (Post 3162980)
Did you catch the error(s) on the 25Z6 supply in the Sams that I linked?

jr

I did not study it real closely...BUT I thought I saw a cap connected wrong--for a doubler--and perhaps a couple MORE backwards on the filter section?


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