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Old September 23rd 06, 05:32 AM posted to rec.radio.amateur.antenna
John, N9JG John, N9JG is offline
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First recorded activity by RadioBanter: Aug 2006
Posts: 83
Default Use of lattice line to feed dipole

You probably should read the article yourself, but Table 1 of the article
contains columns for matched line db attenuation per 100 feet for dry and
wet lines. This set of data is from measurements made at 50 MHz. Since
attenuation scales as the square root of frequency, I came up with a rough
estimate for loss at 7 MHz. The author then goes on and uses modeling to
predict some surprisingly large line losses for the G5RV antenna at 1.9 MHz.

"Owen Duffy" wrote in message
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On Sat, 23 Sep 2006 00:48:43 GMT, "John, N9JG"
wrote:

An excellent article. It appears to indicate that at 7 MHz a feed line
made
from 100' of Wireman 554 window line would have a loss of about 2 db when
the line is wet. When the line is dry, the loss is insignificant.


Is that the matched line loss you are talking about.

These lines aren't always or even often operated at very low VSWR, so
it may be unwise to dismiss the loss as insignificant in the general
sense.

Owen
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