Westinghouse H-196 restoration

[bandersen]

I got my hands on the Sams for the DX version and everything matches my set Now I get to undo a few changes I made and get back on track

[bandersen]

Recapping is complete and I'm moving on to final checks and testing the tubes.


Perhaps I should put these bugle boys on ebay rather than back in the set

[bandersen]

The 5U4 was burned out. I'm guessing from a filter cap shorting out. A couple of the 6AQ5s and a 6AL5 were dead too. Replaced them and finally ready for a power up!


Well I got a nice raster, but no video or sound. Just a faint crackle out of the speaker. I'm thinking something is wrong in the tuner or first IF since the sound is picked off after that stage.

[bandersen]

I poked around the tuner and found what appear to be a damaged component. Luckily it's easy to unmount. While undoing the connections I noticed they were a little sloppy which makes me think it had been removed before.



Sure enough, there's a damaged 0.47 pF RF coupling cap. Not sure of the material but I'm guessing ceramic.


I seems the only modern replacement option is surface mount ceramic
http://www.mouser.com/Passive-Compon...scv7?P=1z0vqin

[rrrhre2s]

Originally Posted by bandersen

I poked around the tuner and found what appear to be a damaged component. Luckily it's easy to unmount. While undoing the connections I noticed they were a little sloppy which makes me think it had been removed before.

Sure enough, there's a damaged 0.47 pF RF coupling cap. Not sure of the material but I'm guessing ceramic.

I seems the only modern replacement option is surface mount ceramic
http://www.mouser.com/Passive-Compon...scv7?P=1z0vqin

Looks more like it has been ground away (to change the capacitance), maybe been that way from manufacturing since don't look like the connections were disturbed and the metal around it is not damaged.

Just thinking ?

rrrhre2s

[bandersen]

Perhaps, although it's used to couple RF so I wouldn't think it's value would be that critical.

I dug out my B&K 1077B and fed a signal right at the tuner output and got a stable image


Didn't last long though because a new issue has cropped up. The horizontal oscillator stops running after a few seconds and the screen resistors starts to cook. The original resistor was charred so I suspect I still had a bad component lurking somewhere.

[bandersen]

It seems this set is finicky about 6BG6s. After swapping four I found one it was happy with and no more raster loss.

Adjusting the controls resulted in a more stable image too. Still bypassing the tuner though.


I then moved on to troubleshooting the lack of sound. Feed an audio signal into the volume pot and got nice clear sound out of the speaker. Tried doing an alignment next and got nothing coming through. Eventually tracked it down to a dirty 2nd IF tube socket

Now back to the tuner. 2pF is the smallest cap I could find so I popped it in the tuner.


After some confusion with the counterclockwise channel numbering, I was able to tune something in


Tightening a loose connection finally produced a clear picture. Horizontal sync is really bad, but so glad to finally have video and sound

[bandersen]

Next a little experimenting with a 7ABP14A military CRT I picked up on ebay. Aluminized, electrostatic focus, compatible basing and voltages.

I was hoping it would make a good test CRT and it does. P14 is a purple/white dual color, dual persistence phosphor produce an odd, but watchable image,

[bandersen]

Moving on to cabinet work now and boy does it need some!
Loose plywood laminations and veneer, veneer loss and badly flaking finish.


One thing working in my favor is that the front trim and safety glass come off easily.


The glass is in very good condition except for one spot in the upper right and some deterioration along the bottom.


Once the glass was flipped over, I discovered the source of both.
The deterioration is caused by the old cushioning material and the spot by a loose screw from the bezel.
The corrosion on the screw makes me think it fell out long ago. Maybe even way back when the cabinet was made.



Let the clamping begin!

[bandersen]

Clamping continues. Pretty much every edge on the cabinet has some separation.


These swivel clamp jaws are very handy for gripping shallow edges.

[Findm-Keepm]

Bob,

You are denying the Smithsonian one fine restorer by hanging out here!

I'm impressed, as usual.

[bandersen]

Thanks! I do what I can

The speaker is mounted facing up on a removable curved board wrapped with perforated sheet meal painted to match the finish. Not very elegant - almost looks like an after thought. The speaker cone sure is dirty.







I replaced a whole strip off the back with new veneer. That results in a much cleaner repair than trying to splice in two triangular patches.

I say "new" veneer, but it's really vintage veneer salvaged from a damaged console set.


Trimming off the new veneer with a specialized saw.


It will match much better once stripped and refinished.

[bandersen]

That leaves repairing a few chips on the front. The detachable frame allows me to hide some repair splices.







Finally time to start stripping!

[DavGoodlin]

Great progress. Saving removed veneer is a good idea, where else can you get a wear-matched piece? I took a big piece off a cabinet top with a steam iron and it looks as weatherbeaten as the surrounding veneer on most anything 60-70 years old.

[bandersen]

Thanks! Here's a section after stripping where the "new" veneer is along the bottom. The grain and coloration is a great match