The final connection from the rig/amp to the feedline in a rover situation can
be messy and subject to shifting or even pulling the rig out the window if you
hit a tree limb
The other issue is knowing if you are putting out power and your swr is stable.
There were many contests that I discovered after returning home that I was
CQing without any power out.
One solution is to use Bird 43 meters, but separate the sensor element (line
section) from the meter.
Bird once sold a nice mounting bracket that fits over the ugly and ungainly
line section. I had access to a number of line sections, so I just mounted
them all on a 3 x 36 x ½ in board behind the rigs in a vertical position (QC
connector to antenna pointing up, QC connector to rig/amp pointing down.).
Using QC adapters, I could select my coax termination type (N, uhf, 5/16 DIN)
and easily calculate the exact cable length I would need from the outside
antenna to the line section board. If any of the antennas ever came loose and
dragged down the highway, the tension was on the line section connector that is
a lot cheaper to replace than a TS-2000 or FT-290MkIII. You can route the
output from the line sections to one meter and switch between bands or use
multiple meters. I chose to take the meters out of the Bird cases and stack
them vertically in 3 inch long cylinders of sch 40 PVC plumbing pipe. You
could probably also use the W1GHZ bargraph meter sold by DEMI in lieu of a 30
uA Bird meter movement.
By having all the line sections in one place, selecting and matching the right
length of coax from the rig/amp to the line section location is a piece of
cake. It allowed use of 18 inch jumpers of Andrew ½ inch hardline with right
angle N connector on one end to go from the rig to the line section/feedline.
If you are caught in a thunderstorm, disconnecting all the coax feeds can be
accomplished rapidly since they are all in one place and accessible.
I used a Chevy Astro that had a flip out side window that popped open about 3
inches at the bottom. That was enough room to route all my feedlines and
rotator control cable into the vehicle. I them cut pieces of closed cell foam
like the kind sold as kneeling pads for gardening and sealed up the 3 sides of
the swing out window. A nice dressing of duct tape (replaced several times a
season due to UV degradation) provided a weather tight seal. I never worried
about security. I figured if someone wanted to break into the van they would
find a way regardless of my security plans.
Why am I telling this story? The line sections I used are excess to my needs.
I just had my second knee totally replaced and will be out of rover action for
at least a season or two. I am selling the line section, mounting
frame/bracket, and Bird connecting cable/adaptor (you select 3, 10 or 20 ft
length), and 2 QC connectors (you specify N, uhf or 5/15 DIN) as a package for
$120 and I will pay cost of shipping in the CONUS. All items are in like new
condition and I am the original owner. Look at my ads posted at QTH.com
swaplist for pictures.
John B. N8UM Oak Ridge, Tennessee
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