[julianburke]

The 29JC20 chassis delivered very nice color pictures with a sulphide (green) screen. Back in the '60's I used to go to the Zenith schools when they would come to Knoxville and Graybar Electric would host these as they were the regional Zenith distributor. The Zenith field engineer we called "the Dutchman" would tutor these classes. He would always refer to the 29JC20 and his young son was touted to be a 29JC20 expert!


As for the "cloverleaf" convergence plastic mount, it was always a problem even way back then. Its' main drawback was that is was not "adjustable" with a screw clamp mount and it was the dickens to reinsert the coil & magnet components in this plastic ring that was not flexible. In doing so it always felt that you were going to break it. The worst part was to replace the completed assembly on the neck of the tube as it was VERY VERY TIGHT! If you had a loose CRT socket, you could also crack the tube or break one or more of the wires underneath to further the hindrance. Time, age and heat would always make it brittle and break as it had a short life span.


As for removing the faceplate on a bonded face, a rebuilding plant that I would work at on nights and weekends, we would place a clean scrubbed tube facing a large (2' X 2') natural gas radiant heater (about two feet away) and after about 10-15 minutes we would place it face up on a wooden box with a one foot hole and take piano wire with a wood dowel on each end then place your knee against the tube and pull the wire between the faceplate and tube and pull. Be sure to wear heavy gloves when doing this not to mention handling the hot tube from the radiant heater. It would slice through with ease. I DO NOT recommend using a hair dryer or heat gun as this will create hot spots on the glass as the heat applied must be uniform throughout the whole glass area and can be dangerous as if you get a very hot spot on the tube itself as it likely can cause the tube to implode depending on the ambient temperature of the area. Moving the heat gun around on the face is usually a losing battle as when you move it around, the spot you just heated will cool rather quickly as there is a large mass area on the face.

I hope this answers a few questions here.