Interesting thread.
Mike wrote:
>I still think it is the length of the cable. Has anyone tried
> to measure > current and voltage when under load e.g. when all four
elements are
> being adjusted? I think there is a voltage drop, which is why the
> controller malfunctions. Wire has resistance and a lot of wire has
> more resistance which has to be overcome.
>
> Have the Steppir folk actually tried driving a four element with 500
> feet plus of wire?
-0-
Joe wrote:
If it were me, I would replace the switching supply with a
simple analog/linear supply using a 24 volt transformer,
a 5 Amp bridge rectifier and 2000 uF of filter capacitance.
With no electronic shutdown/foldback one could confirm that
the problem is higher than expected peak currents causing
the switching supply to shut down.
-0-
Ron pointed out the size of the cable as an issue.
-0--
>From my perspective, Mike's question...has SteppIR actually RUN a 500'
cable...is key. So is his point about measurement. I'd like to see a
scope on the pulse trains, to see what's happening to the stepping pulses.
Joe's idea about an alternate power source has merit...but only if
SteppIR agrees that it won't void the warranty.
Personally, I think Ron is onto the answer. My 3 el was at the end of a
200' run of cable, and I went with the heavier gauge wire. I'll bet that
an even larger wire size will prove necessary for 500'...or that the
capacitance of the longer cable is such that you CAN'T drive the antenna
over that length, regardless of IR drop, and that the Mertel's haven't
actually tested that long a run.
N2EA
Jim Jarvis, President
The Morse Group, LLC
We create high-performance organizations.
jimjarvis@themorsegroup.net
www.themorsegroup.net
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