'51 Zenith Porthole

[Charlie]

Recently, I've acquired my first Zenith Porthole... Model H2438R from 1951 with the 24H20 chassis.

The wood is in good condition, however the finish is lacking. Most of the finish has come off the top and the base... needs to be sanded down and refinished. No big deal... this cabinet will be pretty easy to make look nice again.

The chassis was very dusty, but a couple of make-up brushes and the vacuum cleaner got things pretty clean. Under the chassis looked pretty good. On top, there's been some tubes changed. Most of the tubes are the original Zenith tubes, and the replacements are all RCA and it appears they may have been all changed at the same time. The flyback looks good.

I suspect it's possible the yoke has been changed. The wires to the yoke were still quite bright with color and little if no dirt. Also noticed the the paint has been broken on screws used for evidence of tampering.

The CRT has been replaced with an RCA Silverama and tests EXCELLENT on my B/K 470! The meter nearly goes all the way to the top of the scale! I really like that! I kinda suspect the CRT may have been changed at the same time as the chassis tubes.

The guy I got it from told me he bought the set 15 years ago, and has turned it on from time to time. He said he quit turning it on five years ago when the power cord's insulation start cracking and falling off.

I'm considering pulling the HO tubes and bring the chassis up slowly to see if I can get any life out of it, and if all goes well, plugging the HO back in to see if there's any light on the screen. Of course, the chassis will get recapped, but being that everything looks good, I'll attempt getting a raster only for a few seconds and then shut it down.

I need some input from others that have dealt with metal/glass CRT sets. At the front of the CRT, there's a big grey rubber molding around the edge. I'm going to assume that this molding acts as an HV insulator between the CRT front lip and the metal bezel on the front of the cabinet. Being that the front of the CRT is only about an inch from the rear of the metal bezel, I'm guessing that rubber molding keeps you from getting zapped by the front of the set. Right?

I notice that my Raytheon Porthole set uses this same rubber molding in the same manner.

Here's my concern: The rubber molding around the CRT front has developed several cracks (see photo). With this in mind, I'm afraid there could be some HV leakage and cause an extremely unpleasant shock from the front of the set. After Dave's recent enlightenment, I'm reminded to pay close attention and be very careful.

Question: Am I putting way too much thought into this, or am I right in assuming I'll get a jolt? If I am indeed right, I'm seeking suggestions on how to remedy this molding issue.