Topband: Supporting Ladder line

[Grant Saviers]

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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