4CX250B vs Gi7B families...

Hi Guys,

I am contemplating building a 144MHz power amp and looking at various
options. The obvious solution is a pair of push pull 4CX250Bs.

It appears that the Gi7B and family of Triodes can provide an equally
capable solution. They appear to be much easier to cool, by something
like an Axial Papst Fan (instead of a Snail Blower). The other obvious
advantage is not having to deal with Screen voltage, regulation and
protection. The triodes also look much easier and cheaper to mount
(given the grounded grid). Finally, it seems because of the very low
inter-electrode capacitances, it is quite easy to parallel the Triodes
up as required (even at 432MHz).

So what is the down side for using these Triodes ?

Comments and observations appreciated as usual.

Regards,

Mark.

.

Relevant Pages

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    (rec.radio.amateur.homebrew)
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    ... I am contemplating building a 144MHz power amp and looking at various ... It appears that the Gi7B and family of Triodes can provide an equally ... don't have to neutralize them. ... 4cx250's can use surplus loctal sockets. ...
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  • Re: 4CX250B vs Gi7B families...
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    (rec.radio.amateur.homebrew)