The shield is always the antenna element. The coax provides the signal
return path when the direction is set with the far end as the feed point
of the antenna. Since you likely will have a preamp for the large
negative gain of a RBOG, a few db more from the coax won't matter except
for a few db gain change when switching directions.
Here is some RG174 measured loss data (1db/100')
http://www.dxing.info/equipment/rg_174_coax_bryant.dx
Much RG6 is Copper clad steel (CCS) so how much loss it has with copper
that might be less than 1.8MHz skin depth is an interesting question.
Any data out there? Solid Cu RG6 would be a safer bet. There are many
RG6 variations and ones that are flooded might the best RBOG choice.
Grant KZ1W
On 1/10/2018 3:50 AM, Ryszard Tymkiewicz wrote:
Hi Frank..I understand in the case of BOG we should use both
transformers T1 and T3 with
4:1 impedance ratio... ?
I wonder if it is possible to use RG174 which unfortunately has quite
big attenuation even on 160m?
73 Rys
SP5EWY
A reversible Beverage or BOG can be constructed out of a single run
of RG-6, there's no need to form an open wire line out of two runs
of RG-6,
See ON4UN's Low Band DXing, Volume 5, page 7-88 and fig. 7-118
73
Frank
W3LPL
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