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Re: 75 ohm hardline/feedline





Hi Mark
I tried tied 75 ohm hard for a while, but I did not see any real
improvement
because the transformers added the loss to make the hard-line almost
as bad as 9913.

Then I changed over to LMR-600 ultra flex 3/4 coax.
It did cost more, but solved many problems, including the fact that I
can
use one coax cable for the whole run from radio to rotor without any
splits in the middle.
>From now on, ill skip counting pennies and just throw good 3/4 inch
coax for all 144 and up.
I have been able to cut my coax losses in half.  Now when I key up
UO-14, I do not hear a thing
becaues I have fully captured the reciver and attained a full queiting
signal.  All of the QRM
below my siganl is gone, then I quicly turn down the power.

For HF, I am going to dig up my 213 (which is not water proof) over
the next few years and 
use lmr-400 ultra flex.  


Loss examples 100 feet using the lmr calculator
RG-213 at 	145mc 	2.5 db
LMR-600UF at 	145mc	1.14 db


RG-213 at 	437mc 	4.5 db
LMR-600UF at 	437mc	2.0 db


good luck
miles
(life's to short for QRP)

coax data	
http://www.davisrf.com/comm1/hardline.htm


loss calculator
http://www.timesmicrowave.com/cgi-bin/calculate


mcherry@infotec.com wrote:
> 
> Hello all,
> 
> I have been monitoring this reflector and others for a month or so and would
> like to thank all of you for the information and "polite" participation you have
> provided.
> 
> I am new to this realm of Ham radio and would like to ask a question regarding
> feedline for 144/450 mhz.
> 
> I have about 150 feet of 75 ohm hardline and would like to use it for the
> UHF/VHF antennas I plan to use for satellite work.  I'm sure someone has
> opinions on this v.s. using 50 ohm very good quality coax.  Would like any
> information regarding the use of this hardline.
> 
> Thanks in advance and keep up the good reflector, all.
> 
> Mark, WT6P
> Sacramento, CA
> 
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