Hello Al,
you wrote:
> The problem is that half way through, when it should read 360 it reads 345. 
> There is a nonlinearity in the readout.
>

I made and make the same observation with the KR-600X, the AZ rotor of my 
KR-5600A rotor combination. The KR-600X is completely equal  with  the AZ rotor 
of the G-5400B combination regarding control box and wire poti in the rotor 
(Yaesu took over the Kenpro rotor production and replaced the "KR" by "G").  

When I first added rotor control to my tracking software years ago I mounted 
the  KR-600X in the shack over a big 360° linear scale with 1 m diameter and 
with a pointer that moved around the scale close above it. The rotor ran 
exactly an 360° turn from the starting position  180° in the south to the end 
position 180°. In the software I entered 180 for the start positon and 179.9 
for the end position. I could adjust the meter so that it also moved exactly 
into the start and end position, after I had adjusted the rotor interface poti 
and the "Out Voltage" poti at the control box. . 

Then I entered 360° (rsp. 0°) as target position. The rotor moved exactly to 
that position, the pointer pointed exactly to the opposite direction of the 
starting position.  The meter however pointed to about 342°, so it was wrong by 
about 15° to 20°. The situation is the same until today. The maximum of the 
deviation is in the middle of the scale.

So, by my experience and at least in my case the wire poti in the rotor is very 
linear, but the meter is not. 

I agree with Domenico, that the linearity of the poti is important.  

73s, Erich, DK1TB


  ----- Original Message ----- 
  From: <tok...@myranch.com>
  To: <apbid...@mailaps.org>; <amsat-bb@amsat.org>
  Sent: Sunday, November 25, 2012 10:00 PM
  Subject: [amsat-bb] Re: G5400B Rotor Problem


  > Alan,
  >
  > Thanks for the answers. The rotor goes through its 360 just fine. The 
  > problem is that half way through, when it should read 360 it reads 345. 
  > There is a nonlinearity in the readout.
  >
  > 73,
  > Al W8KHP
  >
_______________________________________________
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author.
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb

Reply via email to