Bill - N3RR wrote:
>First of all do not install the 105BA(S) antennas without modifying them
>to be 105CA(S) antennas. The 105CA design has been computer optimized
>and you will greatly appreciate the several dB gain and front to back
>you will get after installing them as CA rather than BA. The difference
>is mainly in the spacing of the elements on the boom. Just call HiGain
>and buy the manual for the 105CA. You will be pleasently surprised how
>easy it is to modify and how much difference it will make.
Several dB gain? According to HyGain the following is representative
of the Gain and F/B when optimized for the various settings:
Setting Ctr Freq Gain (dBd) Max F/B 2:1 SWR B/W
CW 28.2 8.20 27 dB 1100 KHz
Low Phone 28.4 8.22 27 dB 1100 KHz
Mid Phone 28.8 8.26 27 dB 1100 KHz
Broad Band 28.8 8.20 24 dB 1700 KHz
Max F/B 28.5 7.56 36 dB 600 KHz
Max Gain 28.5 8.60 23 dB 400 KHz
The above settings are not the standard as shipped from HyGain, but
optimized settings for a particular configuration. The difference in
performance between the old 105BA and the new 105CA are not several dB
gain. The CA design does clean up the pattern a bit, but you shouldn't
dive in with unrealistic expectations. The element lengths and spacing
for the above settings are available by pointing your Web browser to:
http://ourworld.compuserve.com/hygain/
73 & GUD DX
de KN0Z Gary
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