it's true, but the imd improvement is minimal.
>Rich,
>
>Maybe I have missed something, you wrote in an article in QST in March 1989
>titled "Calculating Power Dissipation in Parassitic - Suppressor Resistors"
>on Page 26 You stated that "After the amplifier has been tuned for maximum
>output, a slight increase in linearity can usually be secured by increasing
>the amplifier loading - that is by decreasing the loading capacitance -
>until output power decreases by a few percent."
>
>I have followed this guideline for many years and I have always had great
>results.
>
>73
>Pat W1KA
>----- Original Message -----
>From: "2" <2@vc.net>
>To: <wd7s@att.net>; "Phil Clements" <philk5pc@tyler.net>;
><dhearn@ix.netcom.com>; "Bob" <K8MLM@aol.com>; "AMPS" <amps@contesting.com>
>Sent: Monday, August 05, 2002 7:46 PM
>Subject: RE: [Amps] ALPHA 77
>
>
>>
>>
>> >
>> >
>> >> >This "clean" isn't limited to the IMD
>> >> >performance of the amp.
>> >> Harmonics/spurs
>> >> >are also reduced by this
>> >> slight antenna
>> >> >overloading, usually by 5-15dbm.
>> >> >Paul
>> >> >
>> >> ** Heavier loading means
>> >> less load-C. Are you saying
>> >> that less load C
>> >> shunting the output reduces harmonics?
>> >
>> >Yes, this is what I observe on my
>> >analyzer. Lighter loading runs up IG
>> >and doesn't have much effect on the
>> >harmonics or spurs.
>>
>> So a few % heavier loading has no noticable effect on harmonics.
>>
>> tnx, Paul
>>
>> - R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
>> www.vcnet.com/measures.
>> end
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
end
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