I've been playing with BOGs a bit here and am getting good results on
multiple bands. F/B and F/S does vary quite a lot, with some weird
flips in F/B occurring at times--literally changing 180 degrees in
direction. I'm getting good results on 160m and 80m, even though my
current snake length is predictably too short. My 150 foot RG6 BOG
does well on 160 and 80, and weirdly, it is useful on 20m, though it
usually provides a better S/N improvement than directivity there.
I've got a stretching mechanism that allows lengthening the BOG on
demand, to make for better multiband performance. I'm looking to be
selectable from about 180 ft down to 128 ft (optimum for 40m) when the
setup is fully implemented. I will say I don't agree with Luis IV3PRK
regarding the BOG being a resonant antenna. I do see that the F/B
changes with frequency, but not due any particular resonance.
See my QRZ page for build information.
Warren, KD4Z
On 4/17/2016 12:00 PM, K1FZ-Bruce wrote:
>
> ?
> I agree with K2AV that a BOG is a one band antenna if the user is
> looking for the? "highest calibre" pattern, but I have a friend that
> tells me his BOG is also the best 80 meter antenna on his small lot.
> ?
> Because a BOG is a low impedance antenna, it does not couple to other
> antennas easily. (some degree of Isolation.)
> ?
> I have found - some can not get a BOG working, but have also found
> others that can not get a Flag antenna working.? I have friends
> in both of these categories.
> ?
> Another friend placed the null of his flag antenna toward his transmit
> tower to get 'very useable' results.
> ?
> Best results with both antenna types usually come with much research
> and testing.
> ?
> Luis, IV3PRO, at HC1PF spent? a lot of time and research with help of
> others to get his BOGS working really well.
> ?
> Best to read his plotting page first to see his results, then his
> research page to see how he got there.
> ?
> http://www.iv3prk.it/bog-modeling.htm
> ?
> http://www.iv3prk.it/new-page.htm
> ?
> ?
> 73
> Bruce-K1FZ
> http://www.qsl.net/k1fz/bogantennanotes.html
> ?
> ?
> ?
>
> This also makes the BOG a one band antenna for optimum off-pattern noise
> rejection. This is more painfully obvious on the east coast where NE
> orientation for Europe really needs the SW f/b rejection for all the
> southern hemisphere band noise, and for all the midwest/Gulf/Florida
> originating QRN. A well done true Beverage retains all these useful
> characteristics for multiple bands.
>
> A BOG *does* reject close in noise off the sides regardless of electrical
> length at listening frequency, it's just that off the primary band a
> regular Beverage or a BOG cut specifically for that frequency will do far
> better.
>
>
>
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