[Top] [All Lists]

Re: [TowerTalk] Rotator problems

To: "Dan Evans" <>, <>, "VHF Reflector" <>
Subject: Re: [TowerTalk] Rotator problems
From: "Jim Hargrave" <>
Date: Mon, 20 Jun 2011 16:22:19 -0500
List-post: <">>

Sounds like a perhaps a waveform issue.
This is especially critical on rotors that use a
series capacitor on the motor.

The Inverter may not be putting out a good sinewave.
Perhaps it is more like a square wave.
Have you looked at it with a scope?

If it is not a good sinewave, or is dirty, you might be able to
clean it up a little by adding a series iron core choke.
Sometimes a 1:1 isolation transformer or 120 volt variac
will round off the waveform peaks enough for it to work.

    73s de Jim

  > -----Original Message-----
  > From:
  > []On Behalf Of Dan Evans
  > Sent: Monday, June 20, 2011 3:58 PM
  > To:; VHF Reflector
  > Subject: [TowerTalk] Rotator problems
  > I have an odd Rotator problem.
  > In my Rover setup, I have an old Hygain AR40 rotor.   For the past
  > several years I have been having an annoying problem.  Whenever I turn
  > the antenna the rotor moves to the desired position but instead of
  > stopping, as it should, it keeps "bouncing" back and forth several
  > degrees.  And it will keep bouncing until it over heats, or
  > until I shut
  > off the power.
  > My "work around" has been to switch off the power when it reaches the
  > correct heading.
  > While preparing for the June VHF contest I discovered it
  > doesn't do this
  > when plugged into the household 120v outlet.   But it does do it when I
  > use my deep cycle battery and inverter.  So it seems to be a
  > power issue.
  > I don't believe the inverter is the problem.  The rotator is rate at 85
  > watts.  My old inverter was a 100 watt model, and my current
  > inverter is
  > a 400 watt continuous / 800 watt surge.   So it really
  > shouldn't be much
  > of a load...
  > Any ideas?
  > The reason I had it on the bench was to take it apart, check the pot,
  > clean and grease the bearings, check the connections, and replace the
  > rotor cable.  None of which seems to have helped.   I'm a bit
  > stumped.
  > I am considering just wiring up a box with momentary switches for left
  > rotate, right rotate, and a meter for direction....
  > Oh, load on the rotor for my application is a push up mast, and 3 VHF
  > yagis, and cables.  Altogether maybe 30~35 lbs...
  > Scratching my head,
  > 73
  > Dan
  > --
  > Amateur Radio Emergency Service, Clark County Indiana. EM78el
  > K9ZF /R no budget Rover ***QRP-l #1269 Check out the Rover
  > Resource Page at:
  > <>    List Administrator for:
  > InHam+grid-loc+ham-books
  > Ask me how to join the Indiana Ham Mailing list!
  > _______________________________________________
  > _______________________________________________
  > TowerTalk mailing list


TowerTalk mailing list

<Prev in Thread] Current Thread [Next in Thread>