SkyRoof Rotor Control Changes Direction Unnecessarily When Crossing 360 Degrees

[Bob Kmak]

Hello,

I use SkyRoof with a K3NG rotor controller supporting GS-232A and a Yaesu G-800DXA 450 degree rotor. Currently running SkyRoof 1.38. 

I don't remember exactly when this problem started but its definitely been there for the last few releases.

Here's what just happened: I was working SO-50 on a pass that started around 240 deg and went clockwise past 360 to about 15 deg. As the rotor approached 360 it reversed direction and started going counterclockwise like it couldn't go through 360.

There are other cases where this happens but from memory mostly happens when rotating clockwise.

Could this be a HamLib problem or does it sound like the way SkyRoof manages the rotor?

If it helps this is how I start rotctld:

"C:\Program Files\hamlib-w64-4.5.5\bin\rotctld.exe" -m 601 -r COM14 -s 9600 -vvvv

Thanks,

Bob K5WO

[Alex VE3NEA]

@Bob check your minimum and maximum azimuth settings in the Settings dialog, wrong settings there the symptom you have described.

[Bob Kmak]

Hi Alex,

I've attached a screen cap of the settings window.

Just to be clear my rotator has a hard stop at 0 deg when moving CCW. In the CW direction it starts at 0 and moves through a complete 360 deg and continues  to 90 degrees where it stops for the 450 deg limit.

Bob K5WO

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[Alex VE3NEA]

Check if the HamLib driver of your rotator knows abut your rotator's capability to go beyond 360. Instructions how to do this are in the HamLib docs, e.g.,  https://hamlib.sourceforge.net/html/rotctl.1.html - use interactive rotctl.exe (instead of rotctld.exe server) that comes with HamLib to post the dump capabilities command.

[Bob Kmak]

Hi Alex,

I started rotctl with the same params as I use with rotctld and got lucky -- it rotated CW from 200 deg thru 360 and continued CW to 89 deg.

I was worried that I would have to experiment with different values for min and max azimuth because the documentation is a bit confusing on those.

See below for a trace of the rotator movement. It also works as expected in the CCW direction-- passes thru South without stopping and goes all the way to 0 deg.

C:\Program Files\hamlib-w64-4.5.5\bin>rotctl -m 601 -r COM14 -s 9600

Rotator command: M CW
Direction: Speed: 100

Rotator command: p
Azimuth: 249.00
Elevation: 0.00

Rotator command: p
Azimuth: 286.00
Elevation: 0.00

Rotator command: p
Azimuth: 331.00
Elevation: 0.00

Rotator command: p
Azimuth: 5.00
Elevation: 0.00

Rotator command: p
Azimuth: 44.00
Elevation: 0.00

Rotator command: p
Azimuth: 89.00
Elevation: 0.00

Rotator command: q

Bob K5WO

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[Alex VE3NEA]

Hi Bob,

In this log you just tell the rotator to move, without setting the target azimuth. Please try the capital P command and see what rotctl does.

[Bob Kmak]

Here you go. Let me know if you need the more detailed diag trace.

C:\Program Files\hamlib-w64-4.5.5\bin>rotctl -m 601 -r COM14 -s 9600

Rotator command: P 190.0 0.0
Azimuth: Elevation:

Rotator command: p
Azimuth: 44.00
Elevation: 0.00

Rotator command: p

Azimuth: 53.00

Elevation: 0.00

Rotator command: p

Azimuth: 63.00

Elevation: 0.00

Rotator command: p

Azimuth: 73.00

Elevation: 0.00

Rotator command: p

Azimuth: 92.00

Elevation: 0.00

Rotator command: p

Azimuth: 110.00

Elevation: 0.00

Rotator command: p

Azimuth: 127.00

Elevation: 0.00

Rotator command: p

Azimuth: 145.00

Elevation: 0.00

Rotator command: p

Azimuth: 160.00

Elevation: 0.00

Rotator command: p

Azimuth: 177.00

Elevation: 0.00

Rotator command: p

Azimuth: 188.00

Elevation: 0.00

Rotator command: p

Azimuth: 188.00
Elevation: 0.00

Rotator command: S

Rotator command: P 300.0 0.0
Azimuth: Elevation:
Rotator command: p
Azimuth: 201.00

Elevation: 0.00

Rotator command: p

Azimuth: 223.00

Elevation: 0.00

Rotator command: p

Azimuth: 240.00

Elevation: 0.00

Rotator command: p

Azimuth: 265.00

Elevation: 0.00

Rotator command: p

Azimuth: 299.00
Elevation: 0.00

Rotator command: S

Rotator command: P 30.0 0.0
Azimuth: Elevation:
Rotator command: p
Azimuth: 307.00

Elevation: 0.00

Rotator command: p

Azimuth: 330.00

Elevation: 0.00

Rotator command: p

Azimuth: 347.00

Elevation: 0.00

Rotator command: p

Azimuth: 10.00

Elevation: 0.00

Rotator command: p

Azimuth: 26.00

Elevation: 0.00

Rotator command: p

Azimuth: 30.00
Elevation: 0.00

Rotator command: S

Rotator command: q

C:\Program Files\hamlib-w64-4.5.5\bin>

73 Bob K5WO

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[Alex VE3NEA]

Thank you Bob, this was useful. Could you please enable the Log Traffic option in the Rotator Control settings, track a satellite pass that crosses 360 degrees, and send me the log file (Help / Data Folder menu, Logs sub-folder)

[Bob Kmak]

Alex,

Here are the logs.

RS-44 orbit 30576, AOS 14:16  LOS 14:36  SkyRoof v1.38

Bob

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[Bob Kmak]

Forgot to add: AOS: 356 deg, LOS 166 Deg, so the rotator had to reverse direction at 90 deg.

Bob

[Thomas Schuessler]

Does the rotor/software know how to do a flip? Meaning the router would be at  AZ 174° but the elevation would be flipped a full 180 so it would start at the position of the start AOS and continue to flip the elevation back toward 0° by the end of the past. SatPC32 and also the S. A. T. Control box can do a flip like that for the YAESU 5500 and especially the 5400 because that only has 360° of AZ rotation rather than 450. 

TOM N5HYP

Sent from my iPhone

On Jul 13, 2026, at 15:47, Bob Kmak <bob...@gmail.com> wrote:



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[Bob Kmak]

Hi Tom,

Yes the K3NG sw supports 180 degrees rotation of the elevation rotor. I’ve got it set for 90 degrees; the cable management seemed easier. I keep the coax a couple of feet away from the yagis to avoid interfering with the patterns.

73, Bob K5WO

On Jul 13, 2026, at 3:54 PM, Thomas Schuessler <tjschu...@verizon.net> wrote:

Does the rotor/software know how to do a flip? Meaning the router would be at  AZ 174° but the elevation would be flipped a full 180 so it would start at the position of the start AOS and continue to flip the elevation back toward 0° by the end of the past. SatPC32 and also the S. A. T. Control box can do a flip like that for the YAESU 5500 and especially the 5400 because that only has 360° of AZ rotation rather than 450. 

[Alex VE3NEA]

@Tom SkyRoof knows how to flip. Here is a complete description of its rotator optimizations:

https://ve3nea.github.io/SkyRoof/users_guide/smart_antenna_rotation.html

@Bob I have looked at your logs but could not see  a 356 deg -> 166 deg rotation in them. The first log was 59 -> 166, the second one 0 -> 50.

[Bob Kmak]

Hi Alex,

I've collected some of the rotator trace log highlights from the RS-44 pass starting at 14:16  on 7-13-26. File attached.

It looks like everything worked correctly: the rotor moved CW from 339 to approx. 359 and then on to 90 degrees when it reversed direction 

and went around CCW to approx 100 degrees or so then CW to 166.

Bob K5WO

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[Alex VE3NEA]

This is correct behaviour with your settings. If you wire your antenna for elevation 0 to 180 and set these limits in Settings, then even on such passes there will be no 360 deg. rotation in the middle of the pass.