Re: GL-434A tube (specs wanted!)

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Ed Phillips by way of Terry Fritz <twftesla-at-uswest-dot-net>" <evp-at-pacbell-dot-net>

> I also am about to acquire a bagload (literally) of used 4X150D tubes for
> coiling purposes- one thing I want to know is how these convection-cooled,
> high-frequency tubes work in VTTC's and to what extent they can be
> overrated.  Also, since they cost less than the price of many used 811-A's,
> I will try to revisit the concept of an ultra-cheap, small MOT-powered tube
> coil that can be easily built and sold and is very safe.  I suspect this
> tube type would be ideal for "plasma tweeters," one of the few applications
> of the tube tesla coil.
> 
> Thanks for any info regarding the GL-434A.
> 
> Carl

	Don't have anything on the 434A, but some experience with the 4X150
series of tubes.  First of all, not particularly convenient
connections.  Rather fragile when it comes to overheating, and I'd be
careful about the maximum plate voltage.  Probably prone to VHF
parasitic oscillations, particularly if you parallel several tubes to
get more power.  Also, I would prefer triodes over tetrodes.  In spite
of all those words of caution they can probably be made to work OK, but
not as easily as a good power triode(s).

Ed