There is no way i would use those surface mount caps unless you want to see a failure in a day or so. throw them in the garbage.

Why exactly ? Just because they are surface mount ? They'll work just fine.

Justradios dot com has 4 mfd@500 volts. I'm just leery of those type of caps. Keeping an eye on them would be good. If they do leak, be careful. If you are using a Weller soldering station, the goo eats the tips up in less than a day.

Meanwhile, I pulled all the tubes for testing. Unfortunately, careful as I was, the cap broke off the 6JS6 and let the air in :tears:

The tube looked well used and may have been weak, but now I'll never know for sure. I have 1,000s of tubes NOS and pulls but had a heck of a time finding a replacement.

As for the others, I check them with a TC-162 and found many had shorts or excessive grid leakage. Luckily, I had replacements for all on hand.
https://c1.staticflickr.com/5/4249/3...3d625e68_c.jpg

https://c1.staticflickr.com/5/4182/3...8cde6897_z.jpg

While searching I came across this Servicemaster 3AT2 made in Korea. I think it's the first Korean tube I've come across. Don't plan on using it, just though it was interesting.
https://c1.staticflickr.com/5/4268/3...c5fc65eb_z.jpg

Back to the 6JS6 saga. I finally dug up a used one that tested good and popped it in.

https://c1.staticflickr.com/5/4189/3...5e87ffe8_z.jpg

Hmm. Nothing on the screen. Let it run a while and slowly the screen lit up dimly with a weird image.
https://c1.staticflickr.com/5/4194/3...c80c57c8_z.jpg

A while later, it got a little better.
https://c1.staticflickr.com/5/4189/3...1f36dbba_z.jpg

I hooked up by Seco meter and found it was drawing less than 100mA. Schematic calls for 225. Time to search for another 6JS6....
https://c1.staticflickr.com/5/4162/3...04c5faf0_c.jpg

Just as I was about to give up, I found one mixed in with my octal tubes :)

It certainly draws more current, but no HV at first then it suddenly sprang to life and I got a nice, bright image back. At least until I turned it off and back on. No HV, drawing 200mA and starting to red plate!
https://c1.staticflickr.com/5/4243/3...71822a79_c.jpg

I popped it back in the tester and found it has a short. I was able to tap the side a few times and clear it out.
Put it back in the set and it has been been working without trouble for a couple hours.

Even so I'm not crazy about leaving it in the set so took a chance and bought a NOS tube on ebay for $14. I got lucky and it works great!

The image now fills the screen, vertical linearity is pretty good and no more streaking.

I do still need to cleanout the HV cage and fabricate a shield for the HV shunt regulator. Eventually, I'll pull the chassis and go over it too.

Even though it's working pretty well, it's got issues. Like I sporadically loose vertical sync, and focus control is at one extreme, occasional arcing and dirty controls.
https://c1.staticflickr.com/5/4173/3...473e63ea86.jpg https://c1.staticflickr.com/5/4193/3...c2f333265c.jpg

One last thing for now, I stumbled across a NOS channel knob on eBay.
https://c1.staticflickr.com/5/4196/3...ac8693d7_z.jpg

https://c1.staticflickr.com/5/4179/3...d373eb7d_z.jpg

https://c1.staticflickr.com/5/4171/3...24186493_z.jpg

After a bit of a struggle, I got the old knob off. The clear plastic fine tuning was filthy and got a good cleaning.

Here's how I've got the bulb sitting in it's holder. I'm not sure I've got it positioned quite right.
https://c1.staticflickr.com/5/4244/3...15636261_z.jpg

Here's what I got after fighting with it a while. I really need to setup a mirror so I can see what's going on while I position the bulb.

Even so, it's definitely better than before.
https://c1.staticflickr.com/5/4244/3...58f91d64_z.jpg

One of my favorite Zenith channel knobs!!

Nice. You do good work on your set's.

I occasionally lose vertical sync for a couple seconds. Also, the vertical looks like it is about to collapse then clears up. I have never replaced the vertical integrators so maybe that is the problem. The focus control on mine is at the end of its range even after replacing the string of focus resistors. I wonder if this was the case when new. I restored mine ten years ago and I am quite sure I need some new tubes here and there judging by the overall performance is not as perfect as it was before. I need to look on Ebay for spare parts. I would like to have a new convergence cloverleaf as I had to glue mine back together when I first got the set.

Replacing the tubes definitely helped. There is a HV adjustment control. It could be we need to tweak that and our focus would be good mid range on the control.

Has any more progress been made on this set? I'm interested to see how it turned out.

No, sorry I haven't had time for any projects the past few months. I've been too busy with work and fixing up my house.