Topband: 50 ohm direct burial coax cable

[mstangelo at comcast.net]

All,

I'll try out the CATV RG-11 before spending my money on 50 ohm coax.

It will also save me the touble of digging another trench.

Mike N2MS

----- Original Message -----
From: Carl <km1h at jeremy.mv.com>
To: mstangelo at comcast.net, Donald Chester <k4kyv at hotmail.com>
Cc: topband at contesting.com
Sent: Fri, 13 Jun 2014 20:36:49 -0000 (UTC)
Subject: Re: Topband: 50 ohm direct burial coax cable

Ive been using that CATV RG-11 since the late 70's as jumpers to the 
hardline from wire antennas, in the house, and as phasing lines for 160 and 
80M verticals. Never a hint of heat at 1200W but someone with a 3CX15000 
might have a different opinion. Measured loss at 2 MHz was .17dB/100' 
Several lengths are over 35 years old, reused several times MF to UHF, and 
pass regular sweep tests.

Carl
KM1H




----- Original Message ----- 
From: <mstangelo at comcast.net>
To: "Donald Chester" <k4kyv at hotmail.com>
Cc: <topband at contesting.com>
Sent: Friday, June 13, 2014 3:49 PM
Subject: Re: Topband: 50 ohm direct burial coax cable


> Don,
>
> You bring up some good points. I got a couple of hundred feet of Flooded 
> Commscope 75 ohm "RG-11" type at a good proce. I don't have the part 
> number handy. I've been very happy with it at 100 watts. I'm thinking of 
> running 500 watts. The center conductor is copper clad steel. I'm 
> concerned about RF current losses because of the skin effect on 160 
> meters. Does anyone have any experience with this type of CATV cable at 
> high power?
>
> A 1:5 maimatch may be an issue at the amplifier but I guess I can place a 
> L matching circuit between the amp and coax to get the SWR down.
>
> I like Flooded cable not because it is anti-fungal but to keep out 
> moisture. My coax runs 45 feet underground and 20 feet under my deck. I 
> had some groundhogs visiting us under the deck and fortunately they didn't 
> have a taste for the coax. The visitors have been relocated.
>
> Mike N2MS
<snip>