> 1. crank ups and coax (George M. Badger, III)
Hello George et al,
For most HF applications, a good RG213 is more than adequate for feeding
antennas on a crank-up tower. That said, with my Tri-ex W67, I used Davis's
Buryflex: since I sell it, why not use it.
I cycled my tower ever year to lubricate the top bearing and eye-ball the
connections to ensure that they were water tight. The Bury-flex was up for
years and showed no signs of degradation from water or UV rays and was not
damaged when the tower crashed, hi hi.
Standard LMR400 is not the best choice as it has a solid center conductor.
If you want to use LMR, use UF which has a stranded center conductor. The
loss numbers on LMR400 and Buryflex are about the same. Bflex is a bit more
expensive due to its burial grade outer layer of plastic.
When you engineer the coax you have to take in to account the length from
the shack to the base of the tower and then up the tower. I chose to secure
the coax and rotor cable to the standoffs so you had to calculate the
length of each loop. I found this to be better than letting the cable have
free run.
I ran a low loss coax, 9913, from the shack to the antenna switch at the
base of the tower. I then ran Bflex to each of the antennas. I had on this
tower:
Cushcraft:
X-7
5 element 6 meter
19 element 2 meter
146/440 dual band vertical
I can't imagine using RG214 unless you already have it. Especially if it is
silver plate. $$$$$
Good luck.
73, Craig Clark, K1QX
RADIOWARE AND RADIO BOOKSTORE
PO BOX 209
RINDGE NH 03461
603 899 6957
WWW.RADIO-WARE.COM
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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