Yaesu G5400/G5600


I was gifted Yaesu G5400/G5600 and GS-232 (not A or B), 2-Meter and 70 CM Satellite antennas and a Create CR30 Tower. Now the fun begins. I’m a software not a hardware guy. I have the following project in mind. I would like to mount a Raspberry Pi or other SBC on the CR30 Tower to control G5400. The SBC would be connected to a controller (TBD) to track satellites. It would be straight forward to use 5600 and GS232 setting in my shack, but where is the fun in that. I have been searching around for a few days looking for a controller w/o any real luck. What I’m looking for is a controller that ‘combines’ controller and rs232. It does not have to been a single box maybe several ‘boxes’. A kit would be OK, I can solder but not design anything. From my shack I would via WiFi/LAN send commands to the SBC at the tower to move the antennas. Any pointers would are welcomed. Is this a dumb idea? To me this sounds very cool and fun project.



Congrats on the gift! How is the condition of the rotators themselves (thinking of the age and gears here)??

Nowadays, the GS-232 is an overpriced non-necessity, there are lots of arduino based solutions (including one designed by this project). That said, it still has to interface with the controller box that does the actual movement. So, today you could stick the controller box, arduino interface, and SBC (running rotctld) anywhere to run the rotator.

There aren’t any real replacements for the controller box - yet. I’m working on one but it may be a year before its ready for prime time.

hope that helps…


I’m going to setup rotors and test, in the next few days. The rotors/controller have been in storage for 10+ years may or may not work, we shall see. I have been looking at the G5500 shield but can’t seem to find the BOM, the board and software are available. I have done ardunino projects. A controller replacement is the kind of project I have in mind but don’t have the expertise to design one. If the rotors don’t work I’ll get a G5500. I have used a D72 and elk antenna but now want to move to a permanent setup.

I’m interested in any details you can share on your project. SBC based with a hat/daughter board or ardunino?



Great - give me a shout if you run into issues with the arduino shield - we should improve our docs there. The arduino will need flashed with the K3NG controller code, but you will need to change some of the settings (like enabling elevation control in features.h and for some reason the satnogs shield needs pins 7 and 8 swapped in the rotator_pins.h config file)


Here’s the problem with the G-5500 - it is an archaic design (circuit-wise) and was never really engineered for the kind of duty cycle we put the rotator through. On my station for instance, a set of mechanical relays may last 12~ months before the arcing wears them out (think of a spark plug). I’ve replaced relays twice now, and I figured why not try to replace the whole controller?

So, the plan is to do just that, replace the transistor and relay model with a solid state relay set that drives triacs (the motors themselves are 26 VAC). The “design” will be similar to the current controller box, and the idea is to be driven by the K3NG arduino code I mentioned earlier. With this in mind I’ll probably have an arduino daughterboard on the controller PCB, and in that sense it will be arduino based, and plug right in to the raspberry pi via usb on one end, and plug right into the rotor cables on the other.


@azisi has discussing how in principle someone could modify the existing SatNOGS Rotator Contoller hardware (and software) to drive an AC rotator (like the G5500). Maybe it is worth to go towards a universal rotator controller design :slight_smile:


Yeah - I’ve thought a bit about this. Here are some random points:

The G-5500 uses 26 VAC motors, and 5 VDC logic for position reading. Another design difference from our rotator is that the end-stop switches are just that: they mechanically open the circuit providing power to the motor (as opposed to the SatNOGS rotor which takes the end stop feedback). These alone may make this a good idea to “keep separate” from the SatNOGS controller. (otherwise the need for the transformer and triacs would be on the board, unnecessarily for people who aren’t using a G-5500)

The K3NG controller code provides soo much more than what we are making use of today in combination with the arduino shield (and I’m hoping to exploit that in my design). However, we’re only able to use the base functionality with the 32k flash limitation of first gen arduino boards. So, I’m looking into other boards/chips that could be plugged in to this design (and the desire for 5v ADC logic is also limiting as many are going with 3.3v). The added space/pins will allow for display support, push-button controls, and possibly network connectivity (the ‘remote control’ and ethernet code are there, nothing for wifi yet but it could be added easily if we found the right board). Again, if the satnogs rotator controller is designed to be physically right at the rotor, these features may not make sense for it.

(if we were to merge the 2 into one controller, we would have to decide on either extending the satnogs controller code to meet the needs of other rotators, or get K3NG to work with the satnogs rotator. I would highly recommend the latter, as there is so much work already put into that project)

One way this could be solved is to have a main board with 2 daughterboards: 1 for the MCU, and another for a custom board suited to the rotator (SatNOGS steppers, SatNOGS DC, AC)… at this point it becomes so complex that we have to ask if it makes sense to try and do one board?

Left or right, if I continue working on this it will be an open hardware design and we can slap the LSF logo on it. :slight_smile:

@azisi thoughts?


oooh! The crew at remoteqth.com have an open controller design using the K3NG code. However, they are still using mechanical relays, and power is handled independent of the controller. (and it is only azimuth)

Its another talking point nonetheless:



K3NG controller software is non-free (CC-BY-NC). I really wonder how remoteqth can sell these rotator controllers. Maybe they asked for a special license from K3NG or they just ship them without a firmware.


They do not sell w/ firmware AFAIK. (nor would it make sense, really, there are too many settings to tweak that are going to be unique to each station before the arduino gets written)


I setup the rotor and controller on my work bench and they worked. Ordered PCB from oshpark and working on an order for parts. I’ll try to document as I go along, maybe helpful to others. Not sure where I should forum?