Re: wanted-572B tube

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Vardan <vardan01@xxxxxxxxxxxxxxxxxxxxxxx>

Hi Matt,

The 572B will easily replace the 811A and work better.  For a Tesla 
coil, they are very similar but the 572 will be able to push more power ;-)

One thing to be very careful of is many of the e-bay New tubes made 
in China are crap. Many of them will just fall apart or die on the 
first power up.  I would not trust any tube made in China these 
days...  I found this out the hard way...

You really want new Svetlana or an old ham tube someone pulls from a 
radio that everyone knows is good.  Preferably made by someone we 
have heard of like RCA.  If you do have to buy new, RF parts has all kinds:

http://www.rfparts.com/572bprices.html

I see they have china ones too with a 1 year warranty.  It is 
possible they get the "good ones" while e-bay is selling the 
rejects...  One could call RF parts and quiz them for the "whole story" there.

Cheers,

        Terry


At 01:14 PM 5/8/2006, you wrote:
> Hello all,
> my vttc based on an 811A is doing good, but it just gets hot quick. 
> After destroying one 811A(messed with the feedback coil a bit too 
> much, and 500watts on the plate :-D), i have fallen in love with the 
> 572B(from what ive read about it). A graphite plate, high voltage, 
> and most importantly...RUNS ON MY 6.3volt 8amp filament transformer :-)))))
>
> I won a GE 833A triode on ebay, but just hate the idea of a 10vac 
> 10amp filament transformer. Im rewinding a 1kw 60hz toroidal 
> transformer for 10vac right now in case i have to go with the 833A. 
> Ive checked ebay for the 572B, and the majority are pricey NEW 
> chinese tubes. I dont want a new tube, as its going straight to tesla use.
>
> Anyone out there have a few used 572B tubes for a good price?Or want 
> to trade for the 833A?
>
> Thanks!
> Matt