I am forwarding this from the FT-1000MP list for folks who are
still running reduced power on PSK31 :-)
73
Chen, W7AY
Begin forwarded message:
> From: "John" <hydro@naturecoast.net>
To: <rtty@contesting.com>
> Date: Sun Jul 14, 2002 11:34:51 AM US/Pacific
> To: <1000mp@mailman.qth.net>
> Subject: Re: [1000mp] Amps & IMD Low power
> Reply-To: 1000mp@mailman.qth.net
>
> Hi all
> The IMD distortion on 12 volt final radio's goes UP as power goes down.
> The
> MP with 2SC2879 is no exception, It is at it's cleanest when running 100
> watts & ALC is at it's lowest... also by Turning the power down
> increase's
> ALC voltage , which cause's IMD modulation on the controlling FET IF
> amp...
> The radio's that do better when the power goes down are the 28 volt or
> higher final rigs. Turning the rig down to 50 watts or less is the worst
> thing you can do .... A lot of hams don't know this !!! ... Why do you
> think
> Yaesu has the MK5 & Field with a class A low power mode ???
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