If a 7jp4 lights partially, is it ok??

[rca2000]

I acquired this old 7jp4 yesterday, at an auction, where I also got a 7" admiral set, 4 boxes of tubes(MANY NOS, ) and a couple of boxes of RCA parts. (knobs, switches, chips, coils,a crt board, etc)

The Admiral will NOT work, it draws excesive current from the B+(caps, no doubt,) and I could not check the 7jp4 on it. My cr-70 is not working, either, BUT I did get a good filament from the tube on it.

So-- I have another 7" admiral set in the garage, I got about 5 years ago, right after 9-11, IIRC. Figuring there was not much to lose, I dragged it in the house after-hours, (for obvious reasons...)and started it up, without the rectifier tube. All filaments glowed including the 7jp4 in the set. SO...I just "touched" the 5y3 in its socket, while watching the screen--and I got SOME raster!! Plenty bright, but all distorted and compressed into a blur of an inch or two. This means that the tube in the set is pretty good.

Next-- I unplugged the set's tube, and plugged in the "new" one I got. VOILA!! I get a "partial" raster from this one, too. ALL compressed, jerky and bent, but PLENTY bright!! ALL of this took place in the kitchen, under the celing fan light. I had a more than bright enough raster to see in that light.

(Needless to say-- ALL of these tests were only a second or 2 long--as I was fearful of leaving on my set any longer--the very loud hum from the speaker was threatening to wake the girls..and I would have had some explaining to do....but I DID get some raster on both tubes..)

SO...does this mean that this CRT is good? Can a 7jp4 be "bad" even though on a set with problems it produced "some" raster? Will the tube still produce the same decent brightness in a set that is working right??