>
> One suggestion was to install a 4:1 Balun just outside the house to transform
> the open wire feeder to coax. Doesn't this defeat the purpose of using an open
> wire feeder to begin with?
>
> How about using a PVC conduit to route the ladder line to the operating desk?
Yes it does seem to defeat the whole purpose of using open wire feeder.
The assumption here is that since coax is "shielded" then we can run it
through walls, over pipes etc. but think about it: If we connect a
balanced line to coax then rest assured there is going to be plenty of RF
on the outside of that so called shield. So what did we accomplish that we
couldn't accomplish by just running some insulated, open wire through the
wall? Well what we accompished was the introduction of a random, unknown
and sometimes extream impedance to a transformer which will have an
unknown effect on the random mess we fed it resulting in who knows what on
the 50 ohm coax which could have considerable loss on 20m and lower.
In your situation, I would do my best to use balanced line all the way to
the tuner and make sure it's well insulated. 450 ohm window line is fine
and it only needs an inch or so clearance. Running it through PVC wouldn't
help a bit if the pvc is against an electrical conduit. If you ran a 4"
PVC pipe and somehow suspended the line down the center by using tension
somehow then that would be great.
Steve Ellington N4LQ
N4LQ@IGLOU.COM
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