No need to transition. I just use about 2 to 3 turns of the LMR in about
a 12" diameter coil basically laying on the top of the tower. That
leaves plenty to absorb 360 degrees of rotation. In broadcast we do it
all the time with Heliax on live trucks.
Chuck W6RD
On 11/10/2018 7:45 PM, Steve Maki wrote:
LMR400 works well as a rotator loop if you dress it in with a
relatively large hanging loop. Some setups aren't conducive to such a
loop (i.e. top set of guys right at the top of the tower, etc). I
always have 10' of tower above my top guys, so it's no problem.
If you need a tight loop, use RG213 or Davis Buryflex.
-Steve K8LX
On 11/10/18 15:40 PM, Matt Frey wrote:
Looking for suggestions of what feedline to use on the 70' tower. HF
beam
antenna that rotates.
Total length of feedline to the radios would be 100'.
Have been told to use LMR400 or RG123. Need to transition to a more
flexible cable at top of the tower for the rotation?
Should ground the coax at top of the tower and at the surge arrestors at
the house wall 5 feet away?
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