SteppIR says over 200 feet you need the larger cable and the 33V supply.
----- Original Message -----
Sent: Monday, June 11, 2007 10:12 PM
Subject: Re: [TowerTalk] SteppIR problem
> The discussion on this has been very interesting and informative. Most
> the cable length is the problem due to either excessive resistance or
> capacitance. Larger wire would help if the problem was voltage loss, but
> what can you do if the problem is capacitance from the long run? I am
> looking at the SteppIR website and I see only one size 12 conductor cable
> listed. It states that you need a 33 volt power supply for runs over 200
> feet. They should really show a maximum cable length for using 33
> Perhaps with a 500 foot of their cable run you need even more voltage.
> you using a 33 volt supply?
> John KK9A
> To: firstname.lastname@example.org
> Subject: [TowerTalk] SteppIR problem
> From: Bill Carnett <email@example.com>
> Date: Sun, 10 Jun 2007 08:41:54 -0700 (PDT)
> List-post: <mailto:firstname.lastname@example.org>
> Greetings to all Tower Talkers,
> A very wise man and fellow TT (K7LXC) suggested I post
> my challenge here to the group...maybe somebody will
> have a new idea that I've not explored.
> Last week we put up a new 4L SteppIR with a 40/30
> dipole. The antenna is approximately 500 feet from
> the shack. SteppIR control line is used, continously
> without any accessories inserted, running through 3
> inch conduit (not that that makes any difference).
> Prior to lifting it in the air I found that a problem
> existed. When attempts were made to change bands or
> even frequency on the same band, the control box went
> dead. Simultaneously, as the box died, the "on"
> indicator light on the pwr supply went out. A second
> later the pwr light came back on; the led "lights" on
> the control box flashed once but the box remained off.
> The box could be turned back on, but the same
> sequence occurred if a band/freq change was attempted.
> Immediately all of the wiring and continuity was
> checked with the antenna...all ok. Spoke with Jerry
> at SteppIR and we proceeded to change first control
> box....before I realized the pwr supply was
> faltering....no change.
> The next step was to attempt to run each motor
> individually and in groups. Each motor ran
> individually without problem. Adding the 2nd and 3rd
> motor caused no problems....the yagi functioned fine.
> The addition of the 4th motor (didn't matter which
> sequence), consistently killed the antenna. On
> occassion it would all seem to work for a couple of
> band changes but never more than 1 or 2 minutes - with
> all 4 motors running. So, with up to 3 motors
> running...all ok, with all 4, no go. However, this is
> a 4 element yagi. After speaking again with Jerry, I
> was reassured that the problem was simply a power
> supply and all will work fine....thus the long
> scheduled antenna raising event went forward as
> scheduled. Needless-to-say, the replacement power
> supply did not correct the problem.
> Prior to erecting the yagi I extended the elements to
> 14150 so it can be used as a monobander...but that
> will only bring temporary happiness. A power supply
> (3rd) was "hand picked" by the SteppIR engineers,
> sent, and tested this morning. Basically the same
> problem. It did seem to work briefly then shut
> down....exactly the same as before.
> So, I'm looking for ideas that have been overlooked.
> Yes, I should have listened to my gut, rather than the
> "experts" and canceled the raising until all problems
> were fixed, but that can't be undone. If this beast
> must be lowered, I'm a bit reluctant to put it back up
> after this experience. Yes, all antennas have
> problems but it would be less $$ to replace it at the
> time of lowering rather then taking down, bring the
> crane back and forth, etc.
> Sorry for the long-windedness of this but any and all
> thoughts are appreciated!
> 73, Bill
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