[TowerTalk] steppir v. lpda

[jim Jarvis]

This topic is like eating potato chips.

Private communication from N2TK reveals that SteppIR had a supply problem with 
Fernco boots, and used Mission for a while.   The Mission boots have a UV degradation
problem.    My Fernco boots, now.... 10 years old... are just fine.   

On the topic of stepper motor fails,  I would tend to believe that the wiring TO the motor
was at fault, and not the motor.   The weak spot in this antenna is the termination barrier
strips for the control cable, in my view.    It's subject to variability in installation technique.
Statistically, that's much more likely than having a stepper motor fail.   

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On the topic of 200 ohm feedline,  the Tennadyne design uses a 200 ohm feedline BOOM,
fabricated from square tube and spacers.   If there is a weak spot in the design, it lies in 
locating the balun at the nose of the boom, and routing the coax cable back along the lower
limb of that feedline, unbalancing it, and coupling rf into the coax shield.

I fixed that with ferrite chokes at the mast-boom plate on mine.   

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n2ea