Turn the rotor motor unit so that it is at the most ccw position (0
degrees). There should be a couple of index marks on the motor unit that
almost line up when at that setting.
Remove the control unit front bezel, 1/8 th turn anti clockwise, and then
turn the pointer so it is on the zero degree point.
Use the rotor cw direction switch to set the motor unit to 360 degrees,
Essentially when the index marks line up again.
Adjust the full scale pot on the rear of the controller so that the display
pointer is on 360 degrees.
Repeat a couple of times and you should be set.
[mailto:email@example.com] On Behalf Of Rich WA1TRY
Sent: 06 June 2011 05:06
Subject: [TowerTalk] Yaesu G-800S rotor calibration problem
First time here on the reflector. Have been browsing the archives for a
few days now trying to find the solution to my Yaesu G-800s rotor problem.
I bought this rotor several years ago. It was part of a consignment sale
and was told it was never used. And in fact it looks brand new and has
never been installed. I did not get a manual with it. A friend of my has
the same rotor and I was able to borrow his manual.
The problem is that the manual is for three different rotors and the
instructions for testing and aligning don't match the physical
properties of my 800. They are talking about adjustments using a few
pots and a two-position slide switch to turn on and off the calibration.
But my control box only has ONE adjustment (called Full Scale Adj.)
The problem as best I can describe it, is that the rotor and dial in the
control box don't seem to be in sync. I have the rotor on my bench and set
it to one position, say at 0 degrees. Then using the controller I turn the
rotor until it is exactly 90 degrees from it's starting point .. and the
meter reads 70 degrees. I've tested it and when the rotor is physically
pointing at 180 the dial is at 140. When the rotor is at 270 the dial is
I'm hoping some one out there can give me the proper instructions to get
this thing aligned.
I've played with removing the bezel and adjusting the dial, checked the
voltages, also putzed with the full scale adjustment. I don't think it is a
slipping belt (read a lot about that) If it were the belt, then it wouldn't
be out the EXACT amount after dozens of tests. And if it were a slipping
belt, it would have to be slipping in one direction only as when I turn the
rotor back to due north or zero, the meter then shows the correct dial
Starting at zero and running the rotor 360 shows the meter off quite a bit
showing a reading of 290 degrees. But running it all the way back to 0, and
the meter ends up right at zero.
Thanks - Rich WA1TRY
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