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

[Roger <GetValidAddress@xxxxxx>]

On Sun, 21 Jan 2007 01:42:19 GMT, Captain Preshoot
<invalid@xxxxxxxxxxx> wrote:

>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

It's not normally a good idea but not for this reason. Running coax
through conduit, metal or otherwise  does not change the impedance.
The impedance is basically determined by the ratio of the OD of the
inner conductor and the ID of the outer conductor.

>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

There is no such thing as zero VSWR. There is at best 1:1 and I don't
aim for that as I use antenna tuners in the shack to drive antennas on
the other end with over a KW. I'd guess some of the cables easily have
a VSWR as high as 6 or 8:1 .  I can and have run 4 ham stations at the
same time on 1.8 through 50 MHz with no interaction,  nor do I hear
the computers or bother them.

All cables on the tower have the shields grounded at the top and
bottom of the tower. They also come through a grounded bulkhead at the
entrance to the basement.  It's good quality coax, properly grounded
with an elaborate system ground. (32 or 33 eight foot ground rods
CadWelded (TM) to over 600 feet of bare #2) So far I've never had an
instance of cross talk, or one system bothering another.  What shows
up on one cable from another comes in from the antennas.  I'm also
running TV antenna mounted preamps in close proximity to the triband
beam (14, 21, and 28 MHz) as well as both 50 and 144 MHz.  I run the
legal limit (1500 watts output) on 1.8 through 30 MHz and will soon be
doing so on the 50 MHz band. On the 144 MHz band I'm limited to 380
watts into the top beams due to RF exposure levels. However when the
duty cycle is taken into account I could run the legal limit on SSB if
I had the amp. I also run FM and Digital at the same time on the 144
MHz band with a third station on SSB (which is set up in my shop at
present)
Apologies to those who have seen these links before.
http://www.rogerhalstead.com/ham_files/Tower30.htm
Small satellite dish does not show in the photo but it does show how
close the UHF TV  antennas are to the tribander above and the 144/440
vertical below them.  The top antennas in the array are for 144 and
440.  http://www.rogerhalstead.com/ham_files/Tower29.htm gives a
better view of the ham antenna system at the top. It does not show the
wire HF antennas (half wave slopers on 75) or the TV antennas.

>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.

But it works without a problem.

I have TV OTA, TV satellite, FM broadcast, Ham stations (plural) for
HF, VHF and UHF all running together. It may be wrong, but In over 45
years of doing the same thing at different locations I've never had a
problem. The satellite and OTA coax is then bundled with the Cable TV
and broadband coax once it's in the house. When I say bundled they are
taped together to form a nice neat, round bundle.

My grounding bulkhead shown in the bottom photo is no longer in the
house, but all cables come through a grounding bulkhead prior to
coming through the wall.
http://www.rogerhalstead.com/ham_files/cablebox.htm

The first photo shows the cables prior to being "neatened" up a bit.
The second photo shows the mass of cables pretty much as they still
exist.

It may not be good practice but the practice has worked just fine for
me for over 45 years at 4 different locations.

On top of it all the tower has been taking an average of 3 visually
verified lightning strikes a year since it was installed. It took 5
this past summer. So far no damage, but the connectors on top are
beginning to look pretty ratty with all the plating burned off.


>
>---
>Cap'n Preshoot
>Ex. P1-17-11478 (retired comm'l broadcast engr)
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com