I'm currently facing a little problem with our Yaesu controller. I have done all the calibration and the controller appears to be working fine. Unfortunately, it does so for short duration (a couple of hours maybe). After that, the azimuth control goes askew with an offset of around 15 degrees. Therefore I had to recalibrate it almost every time before I try to communicate with any satellite. Could you please provide advice in case you have encountered a problem like this before? I use GPredict and rotctld for all the control.
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- $\begingroup$ Is the calibration done in software, or by adjusting potentiometers in the control box? $\endgroup$rclocher3– rclocher32016-07-18 16:22:37 +00:00Commented Jul 18, 2016 at 16:22
- $\begingroup$ Also, does the controller misbehave even with the computer disconnected from it? $\endgroup$user157– user1572016-07-19 11:43:19 +00:00Commented Jul 19, 2016 at 11:43
- $\begingroup$ Hello. The calibration is done in hardware first and then in software. I recalibrated everything[hw and sw] and it seemed to work fine. However, it has started to misbehave again in both hw and sw. $\endgroup$Moses Browne Mwakyanjala– Moses Browne Mwakyanjala2016-07-21 13:47:50 +00:00Commented Jul 21, 2016 at 13:47
- $\begingroup$ I know this is an old thread but if you are still struggling with this... Does the azimuth calibration change on both the meter and for the computer or only for the computer? $\endgroup$Glenn W9IQ– Glenn W9IQ2017-06-26 17:28:39 +00:00Commented Jun 26, 2017 at 17:28
- $\begingroup$ The azimuth calibration changes on both. $\endgroup$Moses Browne Mwakyanjala– Moses Browne Mwakyanjala2017-07-18 13:59:31 +00:00Commented Jul 18, 2017 at 13:59
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4 Answers
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1 I had the same issue. I adjust the Azimuth every day, then sometimes it fails between 15-20 degrees.
Then I replaced the regulator with a new one. Now it is ok.
- $\begingroup$ Welcome to ham.stackexchange.com! It's nice to get an answer from someone with direct, practical experience of the problem. $\endgroup$rclocher3– rclocher32019-07-28 22:32:52 +00:00Commented Jul 28, 2019 at 22:32
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Sorry for the long overdue reply but you didn't tag your response with my ID so I didn't get notification of your response.
The control box azimuth reading and the computer azimuth reading share a common 6 volt feed from the rotor potentiometer circuit but each has their own calibration pot. If the control box meter reading is drifting from the computer reading after warm up, I would suspect that one or the other of the calibration pots is the problem. Try rotating both VR1 and VR3 back and forth several times through their complete range immediately after spraying with a contact cleaner. Then recalibrate both after they dry out.
After calibrating, leave the rotor azimuth in a fixed position. With a DVM, note the output voltage of the azimuth reading on the DIN connector of the rotor controller after you have successfully calibrated both pots. If the control box meter reading changes, you know that the problem is in that circuit. If the computer reading drifts after some time, re-check the DIN voltage reading. If that has not changed, then the problem is in your computer controller board, not in the rotor controller box. If it has changed, the problem is in the control box circuit that drives the external DIN connector.
Feel free to post your results after going through this troubleshooting exercise if you still haven't found the problem.
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1 I have the same rotor as yours, the Yaesu G-5400B, and it seems like a good rotor. I took it down for maintenance because I had the same problem: I was constantly recalibrating both the azimuth and elevation.
First, I noticed very old and cracked cables, and the terminal blocks on both rotors leave much to be desired in terms of reliability over time.
I removed both terminal blocks, installed high-quality cables and connected them directly (soldering the wires in the correct orientation). I connected a pair of cables to the ones coming from inside the rotor and added a connector to the opposite end of each cable. PROBLEM SOLVED.
But there was another problem. The azimuth indicator, which pointed in a random direction.
The problem was in the rotor's internal potentiometer; it was soaked in oil. It then lost connection to the control box. I completely disassembled the mechanism and cleaned it with isopropyl alcohol. It turned out perfect.
Do a thorough maintenance, including lubrication. You'll have a rotor for many years.
When disassembling the rotor, be very careful with the position of the gears, especially the largest one!
- $\begingroup$ Stackoverflow is, right or wrong, an exclusively English language site. In future, please use English for your posts. stackoverflow.com/help/non-english-questions $\endgroup$2025-04-15 17:39:36 +00:00Commented Apr 15 at 17:39
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3 otra cosa que me olvidé mencionar. Cuando desarmen el rotor tengan mucho cuidado con la posicion de los engranajes, especialmente el mas grande !!
ahora si. Chauuu
73´s dx
Ricardo LU8RM
- $\begingroup$ Stackoverflow is, right or wrong, an exclusively English language site. In future, please use English for your posts. stackoverflow.com/help/non-english-questions $\endgroup$2025-04-15 17:40:22 +00:00Commented Apr 15 at 17:40
- $\begingroup$ As it’s currently written, your answer is unclear. Please edit to add additional details that will help others understand how this addresses the question asked. You can find more information on how to write good answers in the help center. $\endgroup$2025-04-16 02:03:02 +00:00Commented Apr 16 at 2:03
- $\begingroup$ This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review $\endgroup$user3486184– user34861842025-04-16 02:05:31 +00:00Commented Apr 16 at 2:05