Classic symptoms of a bad tube, I think your gut is telling you true.

I seen that tube listed in the classified on ETF . You might want to look there. There was a guy selling a bunch of crts and that was one of them . I think you should be able to locate one .

There's a seller that lists a 23ALP4 on ETF. That looks like it should work. The 23MP4 is listed as a replacement for it.

John

Thanks folks!

I saw the 23ALP4 but wasn't sure it would work.

Is there a standard reference for CRTs showing specs & interchangeability?

That Magnavox is really a beautiful television.

While I was looking at the picture of this set, I could not avoid some thinking to come to my mind: we, the TV collector guys, we are really a very unusual brand of people, aren't we? I take myself as an example. The vast majority of people care nothing about those old TV sets, but me... well, I came to the conclusion that at this point in my life, there's only one thing that makes me feel more enthusiastic about than a nice and rare vintage television set, and that only thing are pretty ladies.

When I am hunting for vintage televisions, it seems like an adventure to me, I go to some very odd places for finding some sets. I almost feel like I were some sort of Indiana Jones, no kidding, because I believe that collecting those old devices is somewhat akin to archeology. I really feel that way, that we are doing a kind of archeological job on finding, rescuing and collecting these TVs. If it were not for people like us, most likely in 50 years from now the only way the people of the future could see a TV set from 1950 would be by looking at photographs.

Have you checked the obvious? B+, HV, and the CRT voltages? If all are within the range of those printed in the Sams, yes, you may have a bum CRT. I've seen CRTs with open cathodes give the same symptoms, but it's best to rule out all other factors first.

Cheers,

I don't know if there's a standard reference. In the Sylvania CRT Technical Manual they list the 23MP4 as a replacement for the 23ALP4. They don't list a replacement for the 23MP4, but I assume it would work the other way. I don't see any differences other than the hearter current.

John

I need to find an HV probe - I haven't had any luck turning one up locally. I am getting HV, but how much I don't know.

Yeah, I think you're right :D When I ask about old TVs or radios at garage sales, I'm usually directed towards something from about 1990.

I'm married now, but it was certainly a lot easier finding pretty girls than vintage electronics!

I stopped to look at a house for sale last week, looks like someone walked away from it 10 years ago. There is a c.1980 Quasar console in the living room - was thinking about calling the realtor to see what else was in there.

My voltages at the CRT are fine, B+ in some places is up to 20% off - I'm waiting for some electrolytics to come in to finish replacing the metal cans.
I do not have a way to test HV - I am getting HV but can not measure it.
I have replaced the HV rectifier, HO and damper tubes.

The pics below were taken in a dark room. Until I can find a CRT tester and/or an HV probe, does anyone have any suggestions of things I can check in the meantime?

Have you tried hitting it with a CRT rejuvenator on the lowest setting? On a tube that far gone, I don't think you'd be hurting anything by trying it.
Some B&K CRT testers/Rejuvenators also have a "remove shorts" setting that is the same as a rejuvenation setting, only not as hard on the tube. If anything, rejuvenating the tube would get you a few more months of an acceptable picture while you look for a replacement tube.

I haven't been able to find a CRT tester/rejuvenator locally - excepting a fairly new Sencore for $500, which is outside of my budget. I guess I'll start saving some dough for one from the auction site.