[Amps] Ameritron AL-572B

gdaught6 at Stanford.edu gdaught6 at Stanford.edu
Wed Oct 22 09:44:37 EDT 2003


On 21 Oct 2003 at 14:25, peter.chadwick at Zarlink.Com wrote:

< snip >

> If looking for low price, you probably can't get cheaper than using surplus
> 4CX250Bs, even though you have to blow them fairly hard. 4 of them will
> give a kW out with reasonable linearity: it may well be possible to put NFB
> on to improve linearity while using up some of the excess gain that there
> would be with a 100 watt driver.

Don't forget the 4x150a!  A fellow at Eimac told me years ago that you could run 
them in the '250 applications, SO LONG AS YOU KEEP THEM COOL.

> (I don't believe they're any good in G-G service)

Probably fine in G-G service, if you use the proper grid supply voltages.  Just hooking 
the screen to the control grid and running them G-G is a very bad idea, though.  
Control grid current is a splatter-generator and a tube killer for these and similar 
tetrodes.

73,




George T. Daughters, K6GT





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