I'd use the LDF4-50 with the N type connectors. From there around the
rotor I use good quality RG-8 or RG-213 with a N connector on one end and
a UHF on the other. At the window I'd change that to a N connector but
not by using an adaptor.
At HF the loss in connectors is not enough to be concerned about. Plus
the N connectors do maintain a constant impedance where UHF connectors do
not. Again, this likely makes little to no difference at HF frequencies
even up to 50 MHz.
I don't use 9913 or any version of the series. I find it to susceptible
to moisture penetration as a result of the type foam insulation used.
{It works better as a garden hose.☺}
I feed my antennas at 144 MHz, 432 MHz and 1296 MHz with 1/2" and 7/8"
hardline fitted with N connectors. For HF I use RG-213 with N type
connectors except when the transition to the UHF style connector is
needed. I use N connectors on the Bird meter so my jumpers are fitted
with N connectors. I do not use adapters.
73
Bob, K4TAX
> As I consider the materials required to replace my 30 year old tower,
> rotor, antenna and cables, I have several like new runs on LDF4-50A
> terminated with N-male which could run from my ground window (UHF female)
> to the top of my 53 foot tower (60 feet max LDF4-50A cable run) where a
> flexible low-loss 10 foot jumper would terminate on a new BN-4000 and new
> TH-7 tribander. This configuration would require the 60 feet max
> LDF4-50A cable run, two half inch N female to UHF male adapters, one UHF
> double female and 10 feet of high quality RG8 cable as the jumper to the
> BN-4000.
>
> The alternative which I?m leaning towards as it seems less likely to have
> connector/adapter loss and other potential problems is a single run of 75
> feet of LMR-400 with factory terminated PL-259s between the BN-4000 and
> ground window UHF female termination. My current installation is 60 feet
> of RG-9913, a UHF double female adapter and a ten foot RG-8214 jumper.
>
> I know the half inch Andrews Heliax has a much lower loss figure (0.357
> db per 100 feet at 30MHz) for a given length versus the same length of
> LMR 400 (0.7 db per 100 feet at 30MHz) , but I?m thinking those three
> adapters (six connection points for loss) and their potential problems
> make it a wash or maybe the advantage goes to the 75 foot run of LMR-400.
>
> I?d be interested in any comments or experiences you might have on the
> subject.
>
> 73 ES DX,
> Gary -- AB9M
>
>
>
>
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