Thanks for the vote of confidence, John.
As I'm sure everyone understands, when we can get help with a project like
this, we want to do it right the first time, since the help to re-do things
can be hard to come by later on.
73 from Tom Behler: KB8TYJ
----- Original Message -----
From: "John Miller" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, May 22, 2006 8:48 AM
Subject: Re: question about coax feed lines
> Honestly, on HF for a short run like that, I'd say you're good with what
> you're doing, for short runs I'd say RG-8X is pretty good anywhere other
> than maybe UHF, the measurements in loss are done in 100 foot runs so like
> with my go kit, for the 2 meter side of things, I run the RG8X since most
of
> my set ups are less than 50 feet, my packet setup runs it and I've tried
> both there and didn't notice much. If it's qualify coax which the brand
you
> mention is, on HF, you're not going to notice any difference at all going
up
> to a heavier coax. Fact is, with HF you could get away with RG8X anywhere
> and if you run 160 and 80 only, RG58 is good enough. Just the way the
bands
> work.
> ----- Original Message -----
> From: "T Behler" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Monday, May 22, 2006 8:19 AM
> Subject: question about coax feed lines
>
>
> > Hi, all.
> >
> > I am finally making progress in terms of getting my new HF Predator
> > screw-driver-type antenna installed onto my RV travel trailer. Hope to
> > have
> > it done by this week-end. ... My question is this:
> >
> > The person helping to install the antenna has already put Belden RG8X
coax
> > on the antenna. The coax run will be about 20 feet, going from the back
> > of
> > the trailer to the inside where I'll have my Icom 718 HF rig. We will
> > have
> > the coax running in a PVC conduit which will run along the frame of the
> > trailer, and the coax will come up through a hole at an appropriate spot
> > inside the trailer.
> >
> > Someone has suggested to me that I really ought to be using thicker coax
> > for
> > this purpose, in order to minimize loss. I do have a 100 foot chunk of
> > RG8U
> > coax with a foam dialectric that I could get the needed coax from, but
> > don't
> > want to go to all the trouble of re-doing the already-existing
connections
> > on the antenna if it really won't make much difference.
> >
> > The guy who installed the original coax on the antenna looked Belden
RG8X
> > up
> > in the ARRL antenna book, and found that it has .7 DB loss per 100 foot
on
> > 10 mhz, so any loss for a 20-foot run would seem negligible to me.
> >
> > Am I ok here, or should I really consider the thicker RG8U stuff?
> >
> > I know there are likely to be a variety of opinions on this one, and I
> > suppose I could always change coax runs later, but I want to try doing
> > things right the first time if possible.
> >
> > Thanks as always for your very helpful advice.
> >
> > 73 from Tom Behler: KB8TYJ
> >
> >
>
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