Predicta - Tube type 21SFA - dangerous?

[Eric H]

Originally Posted by benman94

I just had my first CRT implosion the other day. Definitely treat any CRT with kid gloves.

So what do you think caused this? Temperature difference? did the Dog knock it off the patio? They almost never just implode spontaneously.

[benman94]

The Dachshunds were inside, so it couldn't have been them. Temperature drop too rapidly was the most likely cause. It had been on a tester, cooking at 9 volts, so the neck was very hot. I took it right outside, where the temp couldn't have been more than 40, and was likely closer to freezing. Now that I think of it, scratching the face when I set it on the pavement could have contributed greatly as well. All I know for sure is that I'm never putting duds on the back patio again. I'll walk them right out to the curb on trash night from here on out.

[David Roper]

Originally Posted by benman94

scratching the face when I set it on the pavement

This. A breach in the neck rarely results in implosion, but a nick to the face has always been considered an implosion waiting to happen. Sometimes the wait isn't long. I remember a question to TV Guide's regular tech Q&A column about what to do about a TV screen nicked by a kid's thrown toy. The reader was advised to carefully--carefully--unplug the TV, turn it toward the wall, then run (not walk) to the nearest repair shop.

Safety glass serves a dual purpose.

[Kevin Kuehn]

Originally Posted by David Roper

I remember a question to TV Guide's regular tech Q&A column about what to do about a TV screen nicked by a kid's thrown toy. The reader was advised to carefully--carefully--unplug the TV, turn it toward the wall, then run (not walk) to the nearest repair shop.

Safety glass serves a dual purpose.

I'm surprised they didn't suggest first throwing a heavy blanket(maybe a couple) over the set. In the above case I would think it would have been the safety glass that was nicked. But always better to be safe than sorry. What's scary is that many of us collectors likely have a couple crt's hanging around with scratched faces.

[kvflyer]

Originally Posted by Kevin Kuehn

...
What's scary is that many of us collectors likely have a couple crt's hanging around with scratched faces.

I would be one of those collectors. I have a color RCA CTC-9 "roundie" and a B/W Zenith 12" Porthole with CRTs which test NOS. I just have to get off of my fat arse and restore them.