> I took a look at the info on their site. It concerns me, having a good
> bit of experience with 4CX250B's in VHF amps, that the statement of 50
> watts of drive produces 600 watts out. For a KW DC input the 600 watts
> is about right. However, a well designed pair of 4CX250B's will drive
> into class C with 5 watts of drive. Are they swamping the other 45
> watts? At 50 watts the grids will most likely go up in vapor. Least
> alone the IM produced before the big bang. With today's HF tranceivers,
> most are comfortable at 100 watts output, from where does this 50 watt
> number arrive?
Just another of the hoops an amp manufacturer has to jump through these
days. To obtain type acceptance, the amp must not produce output with
CB style exciters driving them. I am sure there is a pad in the input like
the Henry SS-750 uses (Bird) or some other scheme.
>
> Sure they build a good looking amp, but 2 pieces? Also, I have concern
> that 2 blowers (fans), producing 32 CFM thus more than twice the
> manufactures CFM is adequate. Oh sure that's the blower ratings. While
> Eimac says the 4CX250B needs 5.7CFM at a pressure of .7 inches of water
> at sea level, I wonder how they account for back pressure, other losses,
> in ducts and filters.
> I don't mean to poo poo their amp, it's design or price, but I do have
> concern regarding their intended market. It sure doesn't fit the
> typical "ham" operation as far as amps and drive vs output go.
I say again...I don't think the other amp manufacturers are loosing any
sleep over the new "competition."
(((73)))
Phil, K5PC
> 73
> Bob K4TAX
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