Re: Best brand coax and F connector for HD cable?

[nospam@xxxxxxxxxxxxxxxxx (Alan)]

In article <fkg5r29gcr6m2r2titihv23unaoifi76uo@xxxxxxx> Captain Preshoot <invalid@xxxxxxxxxxx> writes:
>In article <lnoh-1033D3.00404202012007@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> lnh
><lnoh@xxxxxxxxxxxx> writes:
>
>>In article <lkgep2dlnti1q6o350m8oak0pegt1in6m2@xxxxxxx>,
>> Roger <GetValidAddress@xxxxxx> wrote:
>
>>> As to how well  the foil and braid works; I run the cable through
>>> conduit with the cables for my ham station.
>
>Horribly bad practice! Running coaxial cable through metallic conduit will
>change the impedance. Also running transmitter coax alongside receive coax
>in the same cable bundle is a fool's bet and assumes zero VSWR on the
>transmitting antenna. You may be an old-timer, but I've been around the
>track a number of times myself and can tell you, unequovically, what
>you're doing is wrong.
>
>---
>Cap'n Preshoot
>Ex. P1-17-11478 (retired comm'l broadcast engr)


  Since the formula for impedance of a coax does not have any values for
whether it is in conduit or not, I would say your claim is probably wrong.
At the very least, some more supporting evidince is in order.

  Please provide references.


  As for the transmit and receive in the same bundle, you are confusing RF
on the outside of the coax with the RF inside the coax.  SWR mismatch,
does not specifically cause RF on the outside of the coax.  Operating
balanced loads without baluns of some sort would, but that is different
than a simple SWR mismatch.

  Even if there were RF on the outside of the coax, if the receive feedline
is properly set up, it won't be sensitive to it.


	Alan


(And, yes, when I was 19 I studied for an afternoon then spent a couple hours
the next day getting the First Phone license.  The amateur licenses were much
harder.)