[TowerTalk] LMR 900 Question

Dave_K9NX n7ex@athenet.net
Sun, 15 Nov 1998 13:09:06 +0000

At 03:09 PM 11/14/98 -1000, Jim Reid wrote:
>I want to get more of my xmt signal out to the antenna field,  and
>have been thinking about replacing my run of LMR 400 with
>LMR 900 -- it is a lot more expensive than what the 400
>cost,  but also is a lot lower loss.  At $3.76 per foot for
>around 165 feet run,  is this the best way for me to pick
>up10% more xmit signal on 20M,  and 12% more on 15M??
>These are the efficiency increases over LMR 400 per the
>Times Microwave web site cable calculator, 


Seems like a lot of money to pay for a  .4db and .8db increase in signal on
20 and 15.


>Show my ignorance about these some more:  are these
>considered "hard line"  or just lower loss coax??

All hard line is coax not all coax is hardline. The LM series is just coax
since it uses a braid for the shield (plus a foil wrapper). 

I use the LM600DB here for a 300' run and am very happy with it. If you
just gotta spend your money then the DB suffix stuff is worth looking at as
well for a bit more. The DB suffix stands for "Direct Burial" . there is
some kind of "sticky" sealant infused in the braid to prevent moisture from
"wicking" down the braid seems like a very effecient system. About half my
300' run is below ground. Anyway if you live in a high humidty environment
(like Hawaii) you might want to consider this as well even if you are not
going to bury the stuff but just lay it on the ground.

My $.02 worth

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