Antenna configuration:
Yeasu Azimuth and elevation rotor.
Solid fiberglass horizontal mast, 2.00 diameter, 14 feet long.
M2 2-meter (20 element) on one end, M2 440 (44 element) on the other end.
I installed two 80 foot sections of LMR 600-UF from the shack to top of the tower.
I have the option of installing a tower mounted preamp, but just added a Female to female N-Connector at this spot. Preamp are in the Shack.Higher loss, but I have not Fried a Preamp in 15 years.
I installed 2, 20 foot sections of LMR-600-UF is used to go around the AZ/EL Rotor to the antennas (one for each ).
LMR-600-UF is flexible enough to be used around rotors.Just following the bend radius rules for this cable.
Issues:
I used high quality UV-stabilized tie wraps to attached coax to Masts and antenna booms. After 10 years of usage, my SWR went bad on the 2-meter beam.
The vibration and flexing of the antenna boom and rotor masts caused the tie wraps to "SAW" through the outer layers of insulation on the LMR-600-UF.
I had to replace the two 20 foot sections of LMR-600-UF.They were full of water.
Also the 2-meter tuning stubs were also Sawed through by the tie wraps.
I replaced all of the 10 year old damaged cables.
I reinstalled by using Spiral-Wrap over the sections of coax that were going to come in contact with tie wraps. I would add about 4 inches of Spiral-Wrap and then UV black tape to hold the Spiral-Wrap in place.Then I installed 2 tie wraps over Spiral-Wrap.
New Rules.
Never use a Tie-wrap on a bare section of coax insulation (if there is any chance of vibration or flexing). Always cover the coax insulation with Spiral-Wrap to prevent the tie-wrap from sawing through your coax.
On 8/26/2018 8:24 PM, David J. Schmocker wrote:
Hello: New to satellite communication I plan to construct a fixed station to work satellites.
I am looking to identify best type of coaxial cable to run from my VHF/UHF antennas around az/el rotors to the preamplifier (located on the fixed mast/support).
Most important coaxial cable requirements include:
Highly Flexible (in upper midwest climate: temperatures range from �15 deg to +100 degrees F) in Repeated (continuous) flexing Low Loss (while super flex Heliax would be my preference, it�s not designed for repeated flexing this application sees Full shielding (preserve S/N and overall system noise figure).
I can compare the loss values from manufacturer data sheets; my main interest here is to learn what type of cable has withstood the repeated (continuous) flexing required to work satellites?
What cable type do you recommend based on your experience? Thank you 73,
Heliax Superflex? Times Microwave LMR-600UF? EcoFlex 15 Plus? Belden 9913Flex? Something else?
David J. Schmocker, KJ9I
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