grhosler1@mmm.com wrote:
>
> 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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According to the HiGain instruction manuals for the 105BA and 105CA, the
BA has 7.8 dBd and the CA has 8.6 dBd gain; the BA has 20 dB F/b and the
CA has 27 dB F/B (and can be optimized for more). That's where I got
the "several dB", although I sent the last msg from memory and now have
looked it up. The differences between the BA and CA are well worth the
time spent making the changes.
Also, someone pointed out a typo in my last msg: 115CA should have, of
course, been 155CA. It's a 5 ELE 15 Meter beam.
Bill, N3RR
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