In a message dated 10/3/01 2:54:17 AM Pacific Daylight Time, w2cs@ipass.net
writes:
<<
I'm surprised Force 12 doesn't recommend you just replace their antenna with
a dummy load. BW will be improved still further and cost will be kept to a
minimum, although gain and F/B might suffer a tad :)
Sounds like their BW quote depends on there being enough loss in the
feedline to achieve it. Rather strange to say the least!
Gary W2CS
Apex, NC
>>
Longer feedlines do make SWR look better. There is another factor to look
for also. Does the frequency of the lowest SWR change also? This can happen
with some SWR bridges that aren't shielded enough and with Excessive RF Spill
Over from a bum matching system. With lack of proper isolation between the
DE and feedline, the feedline length can affect the SWR in other than loss
ways. I have an all band vertical with that problem also. With clean feed
systems and good bridges I've found it takes a fair length of coax to reduce
the SWR a noticeable amount and there is no change of the frequency of the
lowest SWR.
I had identical bridges for CB that looked well shielded and they not only
gave different channels of lowest SWR but certain ones had it change higher
and then back as I cut the feedline in 6" increments over a 1/2 wave.
What matching system does Force 12 use? k7gco
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