Prototype set is here

[Tom S]

I've been following your progress, that is really a rotton event that should have never happened. Would have been great to see it to the end. I've got a CTC 10 and 11 and I really enjoy them to the fullest. Love the old Tv shows on them. I use both daily. Hope you can find a tube to at least keep it going. Good Luck.

[Steve McVoy]

Tom, Nick has been working with a CT-100 to power the prototype tube. I have his chassis in Ohio, and have been using a 15GP22 with it. Work will continue on the prototype chassis with a 15G, which will work just fine.

[ctc17]

So far I have had a 6GH8, 6JE6 and 21FJ crack and go to air after returning a retired set to service. None of these tubes were being touched, they just went to air while the set was off after I started using the set again.

[Eric H]

Originally Posted by ctc17

So far I have had a 6GH8, 6JE6 and 21FJ crack and go to air after returning a retired set to service. None of these tubes were being touched, they just went to air while the set was off after I started using the set again.

I suppose Glass ages just like anything else, maybe after 50 or 60 years minor flaws become fatal flaws.

[kvflyer]

And I too have had tubes crack after lengthy power off. The CTC-9C that I have had a cracked audio output tube, I think, 6AQ5. Had a 7591 crack and give a really nice purple show as the air leaked in. Now THAT was an expensive tube...

[zenithfan1]

I guess I've been lucky, I've never had a tube go to air. I've found a few in sets that I picked up but never while I've owned them. I better go knock on wood now. I just looked behind me and the CTC 11 that was dropped down the stairs is running in the living room. I use it every day.... I woke it up from a very long sleep.

[joemama99]

I knew you would get that one going,Mark.

[colorfixer]

judging from the basket case 15g that RACS resurrected, I wouldn't think that this tube would be an issue since they would need to redo the neck of the tube to rebuild it in any event.

[tvcollector]

Isn't there a place in France that still rebuilds picture tubes? if so, I'm sure the shipping alone would be outstanding..

[miniman82]

Yes, it's just a simple neck weld. The problem comes from the fact that if the planar dot plate and mask are heated at a different rate than the rest of the tube, the plate can crack or the mask can bend. This is the same issue as with the 15G, but it's worse because the prototype tubes have more thermal mass than a 15G does because its internal supports are heavier. This means even longer bake out times, and more cost. I've read notes from early books on the developmental tubes that state the face should be shielded during cooldown, to avoid cracking.

[miniman82]

Just a reminder to all convention goers, Steve will be talking about the proto set this year and I assume there will be a demo of it working for all to see. Should be an interesting speech, hope I can be there to see it.

[47'Plymouth]

Heyboer Transformers 616-842-5830.they could you one from scratch if you had all of the specs on the power tranformer to run the set..ask for Phil...tell him i sent you..he could make you the filter choke(s) also if the specs on them also... Jody

[Mal Fuller]

I also endorse Heybour Transformer. Here's what I have for contact information:

[miniman82]

What's all the hubbub about transformers?

[Steve McVoy]

I think someone confused the comments about the power supply chassis being missing. The problem is not a missing power transformer - we don't even have the schematic for the power supply chassis.