I was driven to use a quick disconnect 8-pin male/female connector
(Radio Shack Molex(?) type) for the control cables that attach
from the rotor control boxes to the rotor. It is placed within
easy reach, about 18" from the rotor control on each of the two
lines. I placed the female on the line connecting to one of the
two boxes and a male on the other line connecting to the remaining
control box: thereby removing any possibility of getting the two
control cables connected to the wrong boxes.
This allows me to disconnect the cables from the boxes within
seconds (easy slip in - slip out connectors) anytime I am leaving
the operating position or whenever I hear distant rumbles of
thunder heralding an approaching storm.
Further, I use a BNC connector at the back of the Ameritron RCS-4
antenna controller so that, likewise, I can within several seconds
remove the antenna coax from connecting to any of the equipment.
The coax is buried in the yard for 250 feet from the hamshack to
the tower base, providing a relatively low impedance/resistance
path to ground for lightning.
Not perfect, but cheap and effective.
To: <towertalk@contesting.com>
>>Date: Thu, 19 Dec 1996 13:23:49
>>To: Wendell - W5FL <w5fl@flash.net>
>>From: William Barnes <wbarnes@tfs.net>
>>Subject: Re: Feedline and control line protection
>>
>>At 10:49 PM 1/4/97 -0600, you wrote:
>>>
>>>Now I am concerned with the three coaxes (RG173/u or Times LMR400), three
>8 wire control cables for rotator and switches, etc. Polyphaser says to
>ground the shields of the coaxes at the base of the tower, but says not to
>use non hard line coax because moisture gets in when you remove the pvc
>jacket to ground the coax shield. They have very little to say about the
>control lines and they should be important, also.
>>>
>>Take a look at the grounding blocks offered by Industrial Communications
>Engineers in Indianapolis. They are heavy machined aluminum blocks that
>clamp around the coax shield with a mating ground bar to attach to the
>tower. They come with the appropriate anti-corrosion compound to smear
>between the braid and the clamp. They also have other goodies-preamps;
>"lightning arrestors" for coax, open wire, phone lines, and control cables;
>and transformers to use surplus 75-ohm TV hardline. I have not ordered
>from them for some time, but I hope they are still around--I will be needing
>some of the blocks in the spring when my tower starts to grow.
>>
>>I won't add the "standard disclaimer." Hope this is somewhat useful info.
>>
>>73,
>>Bill
>>WB0NSQ
>>
>>P.S. I dug around in the right pile and found their phone number
>1-800-ICE-COMM.
>>
>
>
>--
>FAQ on WWW: http://www.contesting.com/towertalkfaq.html
>Submissions: towertalk@contesting.com
>Administrative requests: towertalk-REQUEST@contesting.com
>Problems: K7LXC@contesting.com
>Sponsored by Akorn Access, Inc & KM9P
Roderick M. Fitz-Randolph
w5hvv@aeneas.net
79 Highland Hills Cove,
Jackson, TN 38305
(901) 661-9278 (Phone - after 10 AM and prior to 9 PM)
(901) 664-7539 (FAX - any time of day or night)
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: K7LXC@contesting.com
Sponsored by Akorn Access, Inc & KM9P
|