My tube and solid state amp has *input* adjustments for all bands. I
suppose these adjustments are designed to compensate for these
mismatches?
>From: "Tom Rauch" <w8ji@contesting.com>
To: <amps@contesting.com>
>Date: 3/10/00 10:20:15AM
>To: "Pete Smith" <n4zr@contesting.com>
>CC: amps@contesting.com
>Subject: Re: [AMPS] exciter to amp coax length
>
>
>> Sure, and in this case the original indicated input SWR was more
>like
>> 1.5:1 than 1:1, hence the length of feedline mattered. I'd still
>like to
>> know why a higher indicated SWR (on the TS-930) translated to
>higher
>> output, plate current and grid current on that one band, but for
>now it's
>> enough just to have things back behaving normally...
>
>Most solid state rigs are conjugately matched at an impedance
>higher than 50 ohms. That's so the rig will remain linear if the
>load
>impedance is slightly above 50 ohms.
>
>The only penalty is excessive current in the exciter's PA stage
>when driving lower impedance loads, and a slight loss of efficiency
>driving low Z loads.
>
>Ignoring SWR shutdown systems, most broadband exciters like to
>see an impedance somewhat higher than 50 ohms.
>
>
>73, Tom W8JI
>w8ji@contesting.com
>
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