Heathkit GR-25/295 thermistors/vdr

[Electronic M]

Unless the old CRT tested bad it was probably savable...There is a sheet of safety glass glued (using transparent glue) to the face of the CRT that acts as implosion protection...The glue degrades over time and loses its transparency, starting at the perimeter of the screen and progressing inward, forming what TV collectors call a CRT Cataract. CRT cataracts are fixable and info can be found here with a search. They don't make or rebuild these tubes anymore so we ought to try to save every CRT that still has good emission.

IIRC Heathkit color sets were RCA based till Zenith bought them out in the 80's. You could probably find an RCA with a similar tube/semiconductor compliment and use a Thermistor/VDR pair from that...At least if someone here doesn't know the right number.