1957-58 Zenith Z2230RZ (Ch. 19Z32) 21" B&W tabletop project log

[cj_reha]

I acquired this set a little over a year ago from a guy who said it'd been in storage for about thirty years and was originally his father's. It's in surprisingly good shape for its age, still has the back as well as four screw-on "legs" to convert it into a floorstanding set. After vacuuming out all the cobwebs, it almost looks new.

There is ONE cosmetic issue, though: a few of the front control knobs are broken. One is snapped in half (the seller gave me the broken piece, funnily enough), another one bent severely and cracked. Is there a good way to remove them so I can use some JB Weld or some other adhesive to glue them back together? They appear to be held on by some sort of locking mechanism (see attached photo), and as they are quite brittle, I'd rather not break more by trying to just pull them off.

I haven't really done much with it besides buying the Sams folder online (set 385, folder 4), and since I'm taking a break from fighting my Predicta, I thought I'd give it a little attention since I've grown tired of looking at it and feeling bad I haven't even touched the insides yet.

First thing I did was to check the CRT with my Sencore CR70. Initial results made me think I had a minty parts set on my hands, as the needle barely moved at all; however, after about ten minutes of letting it cook on the tester, emissions slowly climbed into the good range. There's barely any cutoff, so I'm not expecting a superb picture, but the CRT is at least good enough to the point where I'm comfortable putting time into repairing it.

Next was the hard powerup. I pressed the power button while closely monitoring the tubes and temperature of the electrolytics, and unfortunately, the 5U4 rectifier started redplating almost immediately as one of the cans started getting hot, so I quickly cut the power. I'm assuming a section or two is shorted, and I was planning on restuffing the cans anyway, so it's no big deal.

This will be a fun project! These old Zeniths seem to be very well built, so I expect it won't need much to work again besides lots of caps, maybe a few resistors and the vertical integrators replaced. It's definitely one of the nicest looking sets in my collection. More to come soon, I've got a few other projects hogging my bench right now but they will be wrapped up as soon as possible.