1980 Sears (Sanyo) 25" Console TV CRT Problem

[tv beta guy]

Hello everybody. I've actually been a member since when it was still all Audiokarma. Says since May of 2004. Due to school and such I haven't been active for a long time. I've been lurking on the boards for the past month, which I am quite addicted to. I recognize a few from YouTube here...


Anyhow, I have a problem... One I've never seen before. As in the title, it is a Sears console TV, with a Sanyo chassis.

Finally got around to repairing this TV. All that was wrong with it was a bad solder joint on the coil for the power relay. I fixed that 2 weekends ago.

So I went through the entire TV, redid gray-scale, focus, etc. It was beautiful. The TV looks like it had an honest 25 years or so of use on it until whomever owned it had the problem with the power relay. It was very well taken care of. I got it out of a recycling place.

Anyhow, so I also own a Sencore CR7000. I wanted to test the tube with it.

After I had the CRT neck board off, I accidentally plugged the TV back in. For some reason, the logic decided to turn the TV on with the neck board disconnected. I heard the degauss coil kick on and I just hurried up and unplugged it.

So I test it with my CR7000. Amazing, had 100% emissions still on all 3 guns!

So I go to put the TV back together. When I got several nice arcs inside the neck of the tube while sliding the CRT neck board back on. Scared me, but didn't think anything was damaged.

So I plug the TV back in, turn it on, and I hear a bunch of sizzling when I look back and see the neck of the tube lit up bright purple and orange.

I hurried up, unplugged, cussed.... and then got my CR7000 hooked back up to it.

Every time I tried to adjust the tester for cutoff, a big purple flash would happen inside the neck, and the tester would go into protection mode. The purple flashes were happening further up the neck, underneath the convergence/purity rings it appeared, or under the yoke.

So I'm thinking I just screwed tube up. I was very upset because the tube performed flawlessly and had 100% emissions still.
Went back to G1 short test, and now my blue gun is showing a G1 short. I tried clearing it with the tester, no go. I tried gently tapping on the neck of the tube with the plastic end of a screwdriver and ended up cracking it!!!!

Oh I was upset. Nothing I could have done at this point. So I evacuated the tube, and removed it from the TV.


I found another picture tube, one left, at Video Display Corp. It is a 25VFBP22, which is the same exact tube that was in there. So I just paid $90 + $30 shipping. It just came today, arrived without incident, and my CR7000 shows 100% emissions just testing it. It is supposed to be a NOS tube.


So I spent the time this evening putting the CRT back in the TV. Double and Triple checked my connections.


When I went to test it (luckily I still left my video camera recording), I was greeted with this:

http://www.youtube.com/watch?v=KuNyd...ature=youtu.be


The TV did not blow a fuse. That was me hurrying up and pulling the plug. And if you notice, it still made a loud pop 2-3 seconds after I killed the power. You can see when it popped the screen lit up.

I'm afraid to even turn this TV back on to just see what it is doing. Was it popping because the CRT is 30+ years old and having HV applied for the first time? I shut it off as soon as I heard popping.
I just hope I didn't screw this CRT up because I'll be out $120.

I've never seen this happen before.

All CRT ground connections are in place. No smells, nothing appears to be burnt.

Is there something I should know about these Sanyo TVs that if a certain component fails/shorts/opens/whatever, it will take out an entire CRT like I have witnessed with the original CRT?

I just don't want to power this back up yet without asking and completely destroy this CRT.

Like I said, it did not blow any fuses at all. This is a new one for me.


If anyone has any advice, it would be greatly appreciated.

Thanks.