Non top-cap tubes for plasma tweeters

[bigwill]

Is it possible to use a tube without a top-cap anode to make a plasma tweeter with?
(Such as the one described at http://www.plasmatweeter.de/eng_plasma.htm )

The GU-50 is a cheap powerful RF pentode without a top cap, and since the tweeters are basically big RF generators, will it work, or will the plasma arc straight to the other pins or interfere with the modulation drive? Surely an actual RF transmitter works in a similar way so it shouldn't be a problem, right?

 

[nhuwar]

Don't see any reason why you couldn't, just need a few extra windings on the secondary. After all these things are basically tesla coils.


Nick

 

[nhuwar]

After comparing the specs of a gu-50 to a pl519 I'd say a definite yes on the the use of a gu50 for this application.


Nick

 

[bigwill]

Thanks for your reply

The GU-50 does indeed sound ideal for this application - my biggest worry is the plasma somehow getting on the tube socket pins and vaporising solder - I don't want to breath in lead fumes!

 

[nhuwar]

Ya I don't think you should have to worry about that. And if that happened the tube wouldn't last to long anyways. Your looking at 3 to 4 thousand degrees F for that plasma so it would also make short work of the tubes envelope and bring it to atmospheric.


Nick

 

[okk]

As a plasma tweeter, the voltage at anode not so much high.
Don't worry about the problem between pins.

By the way, did your GU-50 work OK?
Recently, the PL519 expansive too much, GU-50 is a good idea.

 

[bigwill]

Sadly I never got around to it! I really ought to have a go, it's such a simple circuit!