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An ad...

http://antiqueradios.com/gallery/d/146784-2/Ad.jpg

These images are low res for web posting...

At least one of the green dogbone esque resistors (which constitute all the odd ones on my set) are labeled "Germany".

Tom C.

Thanks for the info and the cool ad :) It seems they made this chassis for several years and there were many revisions.

Here's an excerpt from Beitmans 1952.

Quote:

A 12H6 tube may be used instead of a 6AL5 tube for V404 sync discriminator. A 6H6 tube was also used in some sets. The pin numbering for the 12H6 and 6H6 is identical; the 6AL5 pin numbering is different.

When the 12H6 tube is used for V404, an auto-transformer is used to step up the 6.3 volts to 12.6...

If a 12H6 is not available for replacement, a type 6H6 tube may be used if the following changes to the heater circuit are made...

It seems not just resistors were in short supply.

Arg! The copper chassis is missing the IF shield :(

Bob,

Few things:

- Thanks for that update about the filament voltage of the 12H6. I don't have the Beitmans (Do have the Wallace's Telaides) and didn't know it. I will have see if I can find this autotransformer and/or measure the filament voltage of the 12H6. Neither chassis had the 6AL5. But that could easily be changed with the correct wafer socket if necessary.

- I don't think I have the IF shield but will look. I did save some other items like the flyback, yoke etc. from the 16R12 that I had to part out. I got it for the HV cage that was missing from my 26R12. Bakelite cabinet arrived in multiple pieces due to poor (make that non-existent) packing material.

- And I can email the ad in a much higher res to you if you wish...

Ugh, sorry to hear about the smashed cabinet :tears:

I found even more production changes and service notes in Riders volume #8 including the addition of the color adapter in run #6.

The ETF only has a scan from volume 6.

Thanks for looking. If you donlt have the cover, I'll try to cobble something together. My parts order is scheduled to arrive tomorrow just 48 hours after I placed it :)

PM sent with email address.

Quote:

Originally Posted by kvflyer (Post 3010323)

Bob,

I checked. I have the entire IF strip/chassis if you need it. But the damaged set was missing the IF bottom cover as well. Sorry.

I have a yoke, flyback, focus coil, rubber CRT bell cushion, the old electrolytics (for stuffing purposes), the color adapter dummy plug, tuner and a few other items.

BTW,

After the set was working just fine on the bench for about 2 hours, I heard a pop and the picture looked like this. Linearity control was able to fill the screen but linearity was even worse. Height control didn't do much. Changed a few resistors to no avail. I tried a substitute cathode capacitor on the 6S4, thinking maybe it went south. I was disgusted so I let it sit for several weeks.

http://antiqueradios.com/gallery/d/1...BadLin_Web.jpg

Look at the voltages of the vertical section. The problem was staring right at me but I didn't see it. The voltage on the plate of V401A, the Oscillator was 175 Volts instead of 100 Volts. The next key was rotating the height control did not change the voltage. Hmmmm.

http://antiqueradios.com/gallery/d/1...2/VertVolt.jpg

Long story short, one of the guys mentioned tin whiskers. I took out the 2.5 meg height control and cleaned it up. Problem solved. Must have had whiskers!

Now, it works just fine. Just a heads up for your

Thanks for the tips.

The parts have arrived. These plus what I already have on hand should be enough to restore 3 of my Admiral sets which share the same 21B1 chassis: 16R12, 26R12 and 26X56.

First up, the 16R12 tabletop.

http://farm7.static.flickr.com/6027/...f8b1b716_z.jpg

I'll know soon enough if any yokes, flybacks, etc are shot.