-----Original Message-----
From: Vic Rosenthal <rakefet@rakefet.com>
To: Steve Thompson <rfamps@ic24.net>
Cc: Amps reflector <amps@contesting.com>
To: <amps@contesting.com>
Date: 09 May 2000 15:54
Subject: Re: [AMPS] SS750 20 meter test and (maybe) explanation
>
>Steve Thompson wrote:
>>
>> Looking at the gain and efficiency figures, it is behaving normally for
an
>> amp where the collector load impedance is too high.
>
>I don't know if this means anything, but a check of the impedance looking
into
>the coax feeding my antenna (which seems to work much better with the amp
than
>the dummy load) with an ancient Millen antenna bridge shows about 35 ohms.
Of
>course, there's reactance involved, so who knows.
Lower Z at the output socket normally means lower Z at the device terminal,
so it stacks up with what you see in practice.
If you have single band antennas, you could add a fixed matching network at
the shack end of the feeder to give the amp a load it likes, to keep the
no-tune benefit.
Steve
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