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Registered Member #1643
Joined: Mon Aug 18 2008, 06:10PM
Location:
Posts: 1039
I never made a VTTC, which is surprising. I have made multiple SGTC, SSTC, and DRSSTC, but never a VTTC.
I would like to get 1-2ft sparks, from any given size secondary. What tube should I invest into?
The only one I'm familiar with is the GU-81M. But all sellers are outside the USA. We all know world shipping is harsh and brutal, and i have herad people finding broken tubes from outside USA shipping.
So, Where in the USA, can i get a decent tube to do 1-2ft arcs?
IF you live in the USA, and might be able to offer me a tube, please PM me with pictures and price. As a first tube, I would prefer a large one, not a tiny one. Thats why I want a GU-81M so badly, as its big! But I'm afraid it will break on shipping =(
Registered Member #3885
Joined: Sun May 15 2011, 12:47AM
Location: Newton, Massachusetts, United States
Posts: 94
If you live anywhere near Boston, then the MIT swapfest may have what you are looking for. Last time, I picked up an 811A and 572B for only several dollars each for my small VTTC, and I can distinctly recall someone selling large transmitting tubes like the 810.
Registered Member #4108
Joined: Sun Sept 25 2011, 11:43PM
Location:
Posts: 149
I bought a gu-81m and I live in minnesota, mine came in the origanal box, MAKE SURE IT COMES WITH THE ORIGONAL BOX! I have a vttc, I'm doing tuneing, curently i'm getting 8 inch sparks, but I bought a new tank cap and tried it last nigh and got very poor out put
Registered Member #4108
Joined: Sun Sept 25 2011, 11:43PM
Location:
Posts: 149
I bought 2 Nos 833a tubes on ebay, one for $50 and the other for $26 I'm gonna make a vttc out of that, and I have 1 good gu-5b and one dead one, the dead one broke in the mail, so they sent another one and it survived, I think I want to take the heat sink from the dead one and stick it on a gu-5a, I wonder if that will work
Registered Member #4107
Joined: Sun Sept 25 2011, 07:30PM
Location: London
Posts: 53
You might want to try the superb Svetlana 572B. A pair will handle a lot of power - I had 26 centimetre plasma into free air (ie, not to a grounded point) from my VTTC using these - same as length of the secondary coil. The big graphite anodes may glow orange, but red is destructive. power down immediately and tune, or build a PWM and reduce duty cycle.
Incidentally, I've never had problems with world shipping - my tubes came from the US and I live in the UK. I've also bought an 811 by mail order.
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VTTC - Tubes...What to get? Offers?
