I just got a "working" Hallicrafters, and discovered that it had a silver dollar sized patch that blooms with a yellow color at higher brightness levels. I figure that this is a burnt area. I didn't think this kind of thing be very common with a 7JP4, and it makes me leery of buying the used tubes that I have seen available from time to time. Anybody else see this sort of thing? <P>I expect these tubes are going to become more scarce, and I did some looking for rebuilders. I do realize that replacing the heater is one thing and replacing the phosphor is another. Hawkeye is about the only place still around doing rebuilds, and they are not cheap. Anybody know of someone that can rebuild a 7JP4 for less than $200?<P>------------------<BR>

Seems to me that Tucker Electronics, the big after-market test equipment folks, used to rebuild scope CRTs, but I don't know if they still do. They're in the north Dallas area.<P>Dean<BR><P>------------------<BR>

There's a company in Georgia that my dad's company sends off monitor CRT's to get them rebuilt. You might try them. Video Display Corporation (770) 938-2080 or 800-241-5005. They're located in Tucker.<P>------------------<BR>Sean

The 7JP4 does not have an aluminized screen, so you do in fact have an ion burn. However, unlike electromagnetic CRTs, the electrostatic CRTs will deflect the ion beam as well, spreading it out over the scanned area, instead of concentrating it in the center. That's why you'll see a slightly brownish area if you remove the CRT and compare it to the masked off area at the top and bottom of the screen that isn't scanned. It's usually not too bad, however.<P>There's also the possibility that someone operated the set without sweep, using the TV just to hear the sound. That would leave a nice burn mark near the center of the CRT.<P>I don't know of anyone who could rebuild something like the 7JP4.<P>------------------<BR>