At 09:02 AM 12/20/97 -0500, Pete Raymond wrote:
>>I have an AEA SWR121 and it tracks with my Bird wattmeter. One thing that
>I have found is that
>my Alpha bumps up the vswr a little. When the linear is in bypass the xcvr
>shows a different vswr
>reading than if I remove the coax from my switch and measure with the AEA
>unit. Again the reason
>being is that the linear bumps up the vswr a little. Not sure if this is
>your condition but one to
>consider. 73 Pete N4KW, Inverness, Fl.
>
In my case, the amp makes a huge difference. Just measuring with my
transceiver, if I measure through the amp my lowest SWR on 20 falls well
above the band - 14450 or thereabouts - while measuring without the amp, it
falls at about 14200. My Autek tracks very well with the transceiver in
this respect. Quantitatively, the minimum SWR readings are similar, both
with the amp and without. Clearly, these are transmission line
"transformer" effects, intended or not. If your feedline isn't perfectly
matched and a multiple of a half wave at the operating frequency, the only
way to see real resonant frequency is to measure at the antenna. At the
antenna, the resonant frequency is 14175.
73, Pete Smith N4ZR
n4zr@contesting.com
"That's WEST Virginia. Thanks and 73"
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