George:
There is a fine article in THE VHF/UHF DX BOOK publlished by RGSB which
details a pair of 4CX250B's used in parallel for 432 MHz. This
amplifier is known as the K2RIW power amp. The 4CX300A's in parallel
will serve the same form, fit and function with the noted socket
changes.
73
Bob K4TAX
George L Clute wrote:
>
> I should have qualified my question...i.e. running a typical operation of
> 2000 to 2500 DC plate voltage under 250 Mhz in Class AB1 configuration. Has
> anyone constructed three 4CX350A's or 4CX300A's in parallel operation with
> one KW DC input. I suspect from the answers here that it has not been
> accomplished and may be impossible to resonate the plate circuit on
> frequencies above 30 Mhz due to the plate capacitance of three tubes in
> parallel.
>
> Hip boots securely fastened at all times.
>
> George W7LFD
>
> -----Original Message-----
> From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On Behalf
> Of Bob Duckworth
> Sent: Monday, April 23, 2001 4:17 AM
> To: Dfmich@aol.com; amps@contesting.com
> Subject: Re: [AMPS] 4CX350A
>
> Dan-
> You are correct. Tek employed a distributed amp
> as well as some of the early RADAR gear.
> One needs hip boots around here at times :-)
> -bob
>
> ----------
> | From: Dfmich@aol.com
> ...
> | One would have to look at all the gory details to nail this down but I am
>
> | willing to bet that the 75 MHz amp for the Tektronix scope was a
> distributed
> | amplifier. The tubes is such an animal are not in parallel. Rather, they
> ...
>
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