[TowerTalk] (TowerTalk] Lowest loss coax that can be run up a crank up tower

[john at kk9a.com]

I wonder why many hams do not use larger than 7/8 Heliax.  1 5/8 is not
difficult to work with on the ground and it would reduce your VHF band
losses even more. I have a lot of N connectors at my station however if I
were to do it again I would use 7-16 DIN.  Finding a low loss coax for a
crank-up tower is more of a challenge and much depends on how often you
crank it up and down.  

GL
John KK9A


Don Solberg K9AQ wrote:

I have installed a US Tower HDX-572 crank-up tower.  I have two antennas
currently on the tower: 40 M rotatable dipole, and a 2M/70CM antenna for
satellite operation.  My shack is in the middle of a pine forest so the
only way I can get a good view of the sky is to put my satellite antennas
on the top of the mast, which puts it up about 82 feet.

My shack is about 140 feet from the tower.  Currently I have 150 feet for
75 ohm 1/2" CATV hardline running to the base of the tower, and then DX
Engineering's DXE-400MAX running up the tower.  At the top of the tower I
am running RG-213 for the rotator loop and up the mast to a diplexer.  From
the diplexer to a mast mounted 70 CM preamp and to the antenna's I am using
LMR 240.  At the moment I am using a Cushcraft A27010S, mounted at a fixed
15 degree elevation.

I estimate that I have at least 8db of total coax loss.  This also includes
a short jumper from the CATV hardline to a diplexer, the diplexer losses,
and adapters.

While I can work all of the FM and Linear satellites, I would like to
reduce my coax loss.

I ambuyin 7/8" 50 ohm hardline to replace the CATV hardline.  I am also
going to switch to all N connectors and eliminate some PL259 connectors and
adapters.  My plan is also to replace the Cushcraft A27010S with individual
2M and 70CM yagis on a fiberglass cross boom.  When I do that I want to use
lower loss jumpers at the top of the mast, replacing the LMR-240.

My question for the group is what is the lowest loss line that I can run up
the tower and also use as the rotator loop. Is DXE-400Max flexible enough
for the rotator loop?

Is there a better coax to use going up the crank up tower?

Thanks for your recommendations?

73,

Don K9AQ