Al,
The fact that it works OK from S to N but not N to S argues that it is not in the meter electronics. A final test would be to look a the DC output voltage from the DIN plug and compare the two. You will be seeing volts, not degrees, but they should smoothly track, and with a few measurements, you should be able to calibrate one against the other. They get their information from the same 500 ohm pot in the rotator, but different amplifiers. If they track, it is the reference pot. If they don't, it is the meter.
Replacing the pot is not hard, but a messy, tedious job. You used to be able to get the pot from Yaesu for about $10, and there are some places you can Bing which show you how to open up the unit.
73s and good luck.
Alan WA4SCA
-----Original Message----- From: tokens@myranch.com [mailto:tokens@myranch.com] Sent: Sunday, November 25, 2012 3:00 PM To: APBIDDLE@mailaps.org; amsat-bb@amsat.org Subject: Re: [amsat-bb] 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
-----Original Message----- From: Alan Sent: Sunday, November 25, 2012 3:20 PM To: tokens@myranch.com ; amsat-bb@amsat.org Subject: RE: [amsat-bb] G5400B Rotor Problem
Al,
To answer the last question, the "out voltage adjust" is for the reference voltage from the 9-pin DIN connector used with computer control. It has no effect on the meters.
I had that rotator for years, before replacing it about 15 years ago. Unlike some of the other similar Yaesu rotators, the azimuth rotator in the 5400B does not have limit switches, though the elevation rotator does. (See schematic) As I recall, the full mechanical swing is a bit more than 360 degrees, but not the 450 degrees of later units. The stop to stop method doesn't work well. I would set the left limit as you stated, and then visually look at the antenna as you step it to the right. In particular, see what the meter says going through north, then when the antenna swings around to south again. With it fully CCW, find a place in the yard where you are looking down the boom. Raising the elevation to 15-20 degrees will help. Swing it CW 360 degrees and it should look the same. This should be a more accurate way to calibrate the 360. Let us know what happens.
73s,
Alan WA4SCA
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of tokens@myranch.com Sent: Sunday, November 25, 2012 12:31 PM To: amsat-bb@amsat.org Subject: [amsat-bb] G5400B Rotor Problem
Hi all,
Trying to get a G5400B rotor going but having some calibration problems with the azimuth settings. With power off and the rotor set at the left hand position, I adjust the needle to read 180. When the power is turned on the reading goes to about 182. I then let the rotor go all the way to the right 180 mark and adjust the full scale pot to read 180. The problem is when the rotor is half way around and should be reading 360 it actually reads 345. Any ideas on what I should be looking at? Also there is nothing in the manual to suggest what the "out voltage adjust" pot is supposed to do. What is its function?
Thank you for any advice.
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