NoseyNick VA3NNW's Arduino Rotor Controller "Rotorduino"

One day in late 2015, just as winter set in, I found to my dismay that my CDE / Hy-gain HAM-IV Rotor would turn left (CCW) but not right (CW). I didn't know if it was a fault in the rotor, at the top of the tower, the cable down the tower, the control box in the shack, or any of the connectors. I decided I had EITHER a fault in my right-hand end-stop switch (normally closed, opens when you hit the right-hand end, stops you turning any further right to avoid over-shoot damage) or one of the cables / connector pins associated with it. It was certainly acting like I was against the right-hand end (when I wasn't) and thus wasn't letting me turn any further.

I REALLY didn't want to climb the tower until the spring time, but after a bit of diagnosis, a lot of web searching, and a bit of a process of elimination, I decided that yes, that end-stop switch, or some cable/connector associated with it (terminal 5 in the diagram below), was open when it should be closed. I also realised that as a very temporary and very dangerous workaround, I could short terminal 5 to terminal 8, in the control-box on the ground. I could turn right again. I do run the risk of ex$pen$ive permanent damage if I ever run off the right-hand end, but in the meantime I can rotate left and right, and I don't need to climb the tower to fix the rotor / switch / cable / etc.

I put together the diagram below, based mostly on the HAM-IV.pdf manual available from Hy-gain themselves, a CDE HAM-M manual from bunkerofdoom, and the diagram at the bottom of W4ZT's rotor delay page. I wanted/needed something neater than either of those. You are welcome to re-use my version for whatever purpose you wish, with credit / link back to here.

Hy-Gain Ham-XX / TailTwister / CDE / MFJ / many other compatible rotors

I have marked the fault that exists on mine, and my dangerous, temporary workaround. I have not included wire colour info, as I have found at least 3 different colour schemes on the internet and mine seems to be a 4th!

Note: Just to avoid confusion (?), the layout of the terminals on the terminal block (top right) are not the same as the layout in the plug/socket (bottom left). The pins "up the tower" correspond to:

1. COMMON/GND, including compass pot wiper reading
2. brake lifter POWER (2.4ohm to 1)
3. compass pot +ve (520ohm to 7)
4. left limit / motor winding (~5ohm to 1)
5. right limit sw (NormClosed to 8)
6. left limit sw (NormClosed to 4)
7. compass pot -ve
8. right limit / motor winding (~5ohm to 1)

The controller switches...

• CCW(L) shorts 2+6
• CW(R) shorts 2+5

Brake delay, computer control, etc

Whilst I had the controller box open, I was reminded that I have been meaning to automate it a bit better, add a brake delay, etc. There seem to be several options if you wish to buy a ready-made solution (in no particular order):

• Hy-Gain DCU-1 digital controller box, $700 - $750, compatible with the T-2X, HAM-IV, and HAM-V families of rotators. 6 presets, 8sec brake delay, etc
• Rotor-EZ, from Idiom Press / hamsupply.com (Manual) (Schematic). EHam rates this 4.9/5. Popular with several members of my local radio club (KWARC). Price varies from about $142 (kit), $149 (built), +$33 for RS232, Total $182. It adds not just a brake delay and serial CAT control, but has some anti-stick features, a neat status LED that gradually goes red..orange..yellow..green as it approaches your desired bearing, etc.
• Yaesu rotors, various models, various features, various prices. Would require a new rotor plus controller, price looked to be at least $530 total, perhaps well over $1000.
• Yaesu GS-232B $630
• MDS RC1-H, $230, "DCU1 protocol", "Requires 24VAC 125VA Power Pack (or, use your old box's power transformer)"
• AlfaSpid rotors seem to get good ratings, but again would require replacing the whole rotor, and cost about $1000.
• Some TV antenna rotors cost as little as $80, but are really not suitable for the wind load of my TA-53M antenna.
• EASY-ROTOR-CONTROL (ERCv4) is nicely priced at around $64-$90 (kit form), has all the right features, However…
• I figure I could make my own, in the CDE/Hy-gain controller box, with an Arduino which costs about $20-25 (or less) and has USB serial included (USB is much easier than olde-style RS232 these days). Add a 4-relay module (automotive style) which costs less than $10, add a few LEDs, diodes, resistors, a voltage regulator (<$2?), Total $35-40? (20% of a Rotor-EZ!). It would need my own software +TIME (which is obviously PRICELESS!) but would also be fun.

CDE/Hy-gain HAM-IV Power supply

My CDE control box has a 13V DC power supply built in. I was hoping I could connect an Arduino directly to this, but it turns out this (very simple) PSU provides about 37-45mA (or less), adequate for its own ≈27mA pot/voltmeter circuit, but leaving only about 10mA, not enough for an Arduino, never mind Arduino plus LEDs plus relays.

However, the crude resistor+zenner voltage regulator (the R1 390ohm resistor into VR1 Zenner) is easily replaced by something like a cheap 7812 voltage regulator (datasheet). It has essentially the same circuit to control the voltage, PLUS a bypass transistor to provide far more current (see right). Some other specs…

• Over-voltage protection,
• Over-current protection (fuse F1 is less important now),
• Thermal protection,
• +Blah +blah +blah (more than 20 components in all)
• Costs about a dollar
• And all fits in a TO-220 package (like a big transistor)
• Vin min 14.5V (we have about 31V, fine)
• Vin max 35V (close, but fine)
• Vout 12V ±3% (fine for our needs, and Arduino drops it further to 5V)
• Iout max "in excess of 1A", which is plenty. Often quoted as "1.5A" by some manufacturers

"Floating ground" issue and new Azi pot electronics

There's also a "floating ground" issue. Look at terminal 1 in the above circuit. The zenner ensures the PSU rails remain a nice constant 13V apart, but the whole PSU is being pulled up and down (relative to ground) depending on the position of the 500Ω azimuth pot on the right. If the pot is fully right (closest to Terminal 7) the PSU rails (Terminals 7 and 3) are 0V..13V, but if the pot is fully left (closest to Terminal 3) the PSU rails are technically -13V..0V. This has never been a problem for CDE's self-contained azimuth voltmeter circuit, but if we want an Arduino to interface with the outside world via USB, we don't really want that whole USB port being pulled above+below ground. If there's any OTHER path to ground (EG through your PC/laptop) we will be dumping current into places it doesn't belong, not to mention ruining any assumptions about that 500Ω pot being 500Ω!

We don't want to re-wire the rotor itself (at the top of the tower), this might not be physically practical and in any case we don't have any spare wires in the cable/connectors, so we need to take this old pot circuit…

… and replace it with a new circuit where we instead pull both ends of the pot high (typically 5V for an Arduino) through some other resistance (to control current / avoid a short when the wiper is fully-left or fully-right) with the pot wiper still being pulled to GND (0V), like this:

The old circuit is a simple voltage-divider. The new circuit is equivalent to TWO voltage dividers where we are changing the bottom half of the dividers like this (examples for fully left, 50%, and fully right):

• To be generic, we shall call our resistances A, B, C, even if we happen to know all their values.
• We shall also have resistance A=C to be less awkward. These are our pull-up resistors in the controller, it should be quite easy & convenient to have two the same.
• To make the algebra easier, we shall also express the azimuth (X) as 0..1 instead of 0..360. This is "the fraction of B that is on the LHS of the GND"
• Voltages (Y at T3, Z at T7) we shall also calculate as 0..1 ("fraction of supply" units) instead of 0-5V
• Doing the Ohm's law for the voltage divider circuits:
• Y = BX ÷ (BX+A)
• Z = B(1-X) ÷ (B(1-X)+C)
• Solve for X…
  Z = B(1-X) ÷ (B(1-X)+C)
• Multiply both sizes by (B(1-X)+C):
  B(1-X)Z + CZ = B(1-X)
• Divide both sides by B:
  (1-X)Z + CZ÷B = 1-X
• …
• …
• … and trust me I DID work all this out, over about 2 pages of algebra,
• … and got a 2^nd opinion from my wife (BSc Maths, Lond, Hons)
• … and then remembered I could get a 3^rd opinion from the online algebra genius in the cloud… WolframAlpha.com!

Ignore solutions where A=0 (superconducting/shorted pull-up resistors) or B=0 (shorted rotor pot). There are others where X=0 when Y=0 - also fairly obvious. By far the most useful solution is:

Nice! Note A and B have dropped out of the equation too! This means that we don't need to care too much what the values of A and C are (our pullup resistors) are as long as they are the same, and limit current enough to avoid shorts. Nor do we need to care too much what the resistance B is (azimuth pot at the top of the tower) - I was assuming a 500Ω but would work equally well if someone has a rotor with a 1k pot or whatever.

If we DO care, we can also calculate the value of B (rotor pot) given known A=C (pull-up resistors in the control box), and WolframAlpha has given us that equation too:

It also tells us the algebra breaks if 2YZ = Y+Z. This is a fairly obvious "divide by zero", however if we think about the possible values of Y and Z, this condition can only ever actually happen in real life if…

• (Y=Z=1) : The rotor is not connected, or the pot wiper is not grounded
• (Y=Z=0) : Both ends of the rotor are shorted to ground somehow

It makes perfect sense that we can't calculate the azimuth (X) in either of these conditions, and also makes sense to test for both of these conditions in the Arduino code and alarm / signal if we see them.

If we are interfacing with "the real world", in fact electronics that are going to be in the near-field of a transmitting antenna, up a 15m tower, in Canadian weather, we should also add some protection circuitry. We will add bleed diodes to protect against over-voltage (> 5V) and under-voltage (< 0V), and extra resistors between the terminals and the Arduino for extra isolation.

Azi Pot Induction / Shared Ground Issue

The azi pot circuit above works fine when testing with any sensible pot on the bench, but neglects one important issue. The points marked 3 "Y", 7 "Z", and even 1 GND above are not single points, they are long wires out of the control box, across to, and up the tower, the entire length of which are right next to the high-power AC drive circuitry on the other wires (2, 4, 5, 6, 8), carrying enough power to lift the brake, and for the main motor windings to drag around a military-grade TA-53M antenna (or whetever you have on your tower). Some combination of the shared ground, and induction from these 30VAC RMS (≈85V pk-pk) high-current wires, superimposes a significant AC component on top of your little 0-3VDC sensor voltage, any time the brake is lifted and worse when the motor is rotating.

The diagram on the right shows the first version of my AziPot input protection circuitry. I used 500-ohm resistors for the pull-ups (A and C). Diodes clamped the voltage between 0-5V to protect the Arduino, with some more resistors (also 500-ohm, but unlabelled in the diagram) for a bit of current-limiting.

We are trying to measure a DC voltage between 0-5V, or in practice more like 0-2.5V (see the 1st oscilloscope below). With a large AC component superimposed on top, the analog input makes a fairly poor random-number generator, depending on exactly when I sample it (see the 2nd oscilloscope below). I could average a series of readings, or I could add some capacitance into the circuit on the "inside" of the protection circuitry (2nd version of the Azipot circuitry), however my voltage-clamping works against me here - the 3rd oscilloscope shows an example where the AC signal is being clamped at 0V, leading to an artificially high average (or capacitor-smoothed value). In practice this gives erroneously "central" values near the ends of the Azimuth scale (which return to a "correct" reading when the brake/motor are no longer energised.

Arduino control of the meter

The meter (I) in the original CDE circuit is a 1mA ammeter, acting as a voltmeter. It sees 0V / 0mA when the rotor is fully left, 13V / ≈1mA when the rotor is fully right, via a 10k resistor and part of a 5k calibration pot (13V through ≈13kΩ, see?).

We will want the Arduino to control it, partly 'cos it's neat to be able to do things like displaying target bearings and stuff, but mostly because we now need to do the above complicated algebra before we know what to display on the meter. An Arduino PWM port can do "analogWrite(0..255)" which isn't strictly analog, but as far as a slow mechanical meter is concerned, will be a value between 0 and 5V. We will thus need to re-wire the meter from an Arduino PWM pin, via about 5kΩ (preferably adjustable for calibration) to ground. Another option might be a fixed resistor slightly less than 5k (say, 4k7) and deliberately don't analogWrite(255) (5V) but limit to analogWrite(240) (4.7V) or whatever now gives a full-scale deflection

Arduino shield

We are replacing the CDE "R1 390Ω resistor into 13V Zenner" with a 7812 voltage regulator. The F1 fuse, assuming it was just protecting the meter, is now a bit more optional (We still have F2, and all the Arduino's protective circuitry). We are removing the R2 10k to replace with some other 5k pot.

All in all, we are replacing most of the CDE PCB, in fact if we can add replacements for the CR1 rectifier diode and C1 capacitor (470µFD or greater - newer Hy-gain rotors seem to use 1000µFD, and I seem to have 1000µFD 63V in my junk-box), we have replaced the whole CDE/Hy-gain PCB. We need 2 pull-up resistors for our new Azi pot circuit (should compare nicely with the 500 ohm azi-pot - I used 510 ohm), and 2 more isolation resistors (almost any value, i used 510 ohm again) and the over/under-voltage protection diodes (total 4). All this deserves a new PCB, and when Arduinos are involved, it's traditional to build these PCBs in the form of a "Shield" card that sits on top of the Arduino.

Veroboard design

I quite like Veroboard / stripboard. Rather than making your own PCBs with all those messy etching chemicals (or indeed sending off for someone else to do the same), you buy stripboard which is a generic PCB with a grid of 2.5mm holes joined with horizontal copper tracks. You drill tracks when you need to split horizontal tracks into two or more, add jumper wires as vertical tracks, and mount through-hole components vertically between tracks or horizontally between 2 parts of a drilled track.

To be clear, the copper tracks are on the bottom of the board, all components and wires are on the top of the board. The exceptions (in this case) are the long pins going down to the arduino below, and a cunning upside-down socket for my choice of relay module.

Due to an Arduino CAD error, pins 8-13, GND, and AREF don't quite fit the 2.5mm grid, but the pins down to the Arduino are long enough that they can be fairly easily pre-bent, with pliers, to fit (see detail below, right).

I designed the Arduino code to work with almost any pinout, but deliberately used the same pins as the RB-Dfr-170 / dfr0144 relay shields - 2, 7, 8, and 10 (you could stack the Arduino, relay shield, and Rotorduino shield, but may struggle to find space for all 3 in the Rotor box!). The relay board I ordered was not a shield, but had VCC,RLY1..RLY4,GND pins on a row of 2.5mm pins. I found I could position it quite neatly hanging off the bottom-right, diagonally adjacent to my Arduino, but it took a bit of up-across-down fiddling to get a female connector BELOW the board on the "wrong" side of the stripboard (see detail bottom right). If you use a shield with a different pinout (EG RB-See-452) you may need to move some other pins round - this is easy in my software, but would require re-work of the vero shield. Another option would be a ribbon-cable to a nearby relay module (or "un-stacked" shield). My relay module wanted 12V power to (but 5V signals). If you have a 9V module, you could use a 7809 instead of a 7812 voltage regulator, and make no other modifications ot the circuit. If you have a 5V-powered module you can remove the right-most vertical wire from "RLY VCC 12V" down to "12V" and replace with the dotted wire marked further left from "RLY VCC" up to the right of the "5" terminal (which provides 5V from the Arduino).

Most of the space is taken up with a row of grey+blue 5mm-spaced terminal blocks to make it easier to connect into the CDE controller box (I bought about 400 of these terminals for a few dollars years ago) and connectivity to them.

Click "Vero Areas" below for a key pointing out the different areas of the board, corresponding to the same areas in the "Circuit" diagram itself. Click "Vero Details" for a less cluttered view, also explaining some of the connector details. "Photo" is a photo of my constructed board.

The white holes are drilled tracks on the bottom of the board to split the track into 2 or 3 horizontal tracks. The pink holes show the locations of Arduino programming pins - I avoid to reduce risk of shorts.

Circuit |  Vero Areas |  Vero Details |  Photo

Rotorduino shield construction process

1. Cut the veroboard to approx 39 tracks × 26 holes
2. If your Arduino's reset button is next to the USB, you may wish to saw / dremmel a triangle off top right corner (as shown) for easier access. If your reset button is elsewhere, well, sorry, you may need to use the power switch instead
3. MARK all the components, wires, connectors, and hole positions on the TOP (non-copper) side of the board. Use a few different colours of permaent marker
4. Check, check, and check again.
5. Drill the copper tracks (underneath) where marked
6. Solder all the vertical wires (yellow in the above diagram)
7. Note the 5V VCC modification if your relay module requires 5V. DISCONNECT the right-most wire from "RLY VCC 12V" to "12V". Connect the dotted wire from "RLY VCC" up to the "5" screw/spring terminal
8. Bend the pins on one of the stackable headers, as shown, using pliers. There are 2 bends per pin, one right at the vero, one approx halfway down each pin. Test how they fit the Arduino, re-bend if appropriate
9. Note that the Arduino Analog pin header has only 6 pins, not 8. If you bought a big collection of 8-pin headers you may need to trim one to size. Do this by removing and disposing of pin 7, cut through the connector there, and file any rough edges
10. Solder all 4 arduino stackable headers
11. Check the shield plugs neatly into the Arduino. Re-bend any pins if appropriate. Check clearances. Unplug from Arduino
12. For the BOTTOM-mounted header for the relay module, I found I could solder UPWARD-facing pin headers, then push a stackable header (trimmed from 8 to 6 pins as above) adjacent to it, held in place with some of the plastic blocks from 6 more pin headers (pins removed), then jumper the 6 pin-headers to the inverted stackable header. See "Vero details", bottom-right
13. Alternatively, you may prefer to use a single 6-pin header and connect to a nearby relay module with a 6-way ribbon cable.
14. Solder all the screw / spring connectors
15. Solder the trim-pot. There's space for almost any through-hole trimpot.
16. Solder the rectifier diode on the bottom-left of the board
17. Solder the large capacitor. Check orientation!
18. Solder the 2 small ceramic disc capacitors next to it
19. Solder the 7812 (or 7809 for 9V relay modules). It is a little vulnerable hanging off the edge, but should get good air circulation and have space for a heat sink - the 7812 can get hotter than you expect, as it is essentially acting as a resistor dropping your 30V to 12V, arguably wasting more power than the rest of the circuit added together :-/
20. Check there's about 6k of resistance between Arduino pin 9 and the "M" spring/screw connector. Adjust the pot to suit
21. Using a continuity meter, test the entire board for shorts, it is very easy to accidentally bridge adjacent tracks when soldering. Remember there are a few places where adjacent tracks are EXPECTED to be connected, EG A5 to terminal "C", 2 adjacent Arduino GNDs, 2 other GNDs in the bottom-right. Depending on your continuity-tester, the diodes and/or resistors in the top-left may produce false-positives too?
22. WITHOUT connecting the Arduino or relay module, temporarily borrow 30V AC from the CDE/Hy-gain meter transformer (or pins 11 and 13 on the CDE/Hygain PCB). Connect them to screw/spring terminals "G" and "X" (for Xformer)
23. Measure voltages from GND to "(12V) Vin". It should be 12V if you have a 7812, 9V is you have a 7809. Check "RLY VCC 12V" (except if you have made the 5V relay mod). Check there's NOT 12V anywhere unexpected
24. Disconnect the mains.
25. Solder the pull-up resistors (top right, on the Terminal 3/7 tracks). Mine were 510ohm, anything from about 500ohm to 1k should be fine as long as both are the same value. If you have a big collection of resistors, try to pick 2 as close in measured value as possible
26. Solder the top-left corner of the board - the current-limiting resistors (again 500ohm to 1k) and rail-clamping diodes. Be very careful of the direction they are pointing - the idea is NOT to allow current to flow straight from 5V to GND, but the exact opposite - to allow any overvoltage to be dumped onto the 5V rail, or any -ve under-voltage to be dumped onto the GND rail.
27. Check the positions of the 2 left-most vertical (yellow) wires. The (filtered) Terminal 7 comes down to Arduino A2, Terminal 3 to A3.
28. Connect ONLY your Arduino to your computer's USB (NOT to the shield - leave that to one side for now). Use the free Arduino IDE software to load my software onto the Arduino. Check that the debugging LED on Arduino pin 13 blinks (you are in debug mode by default).
29. Open the Serial monitor in the Arduino software (Tools, Serial Monitor, or the little magnifying glass near the top-right). Set it to Autoscroll, any line ending (NOT "no line ending"), 9600 baud (Or see SERIAL_BAUD near the top of my software if you wish to change this). Click in the long box at the top (to the left of "Send"). Hit return a few times. You should see the debugging menu. Type "1" [and return] for a nice Arduino pinout.
30. Unplug the USB. Carefully connect the Arduino underneath the shield. Check for clearance, make sure nothing looks close enough to short.
31. Reconnect the 30VAC. Check for 5V between any G / GND and the terminal marked "5". Remove power.
32. Connect your relay module. Reconnect the 30VAC.
33. Several relays should tick-tick-tick to indicate an error condition (Rotorduino has detected no Azi Pot). Disconnect power.
34. Connect a spare potentiometer (any value 500ohm to about 2k) between Terminals 3 and 7, with the middle connection (wiper) to G (GND).
35. Reconnect power. This time the relays should NOT tick-tick-tick - Rotorduino has detected your fake AziPot so thinks it has a real rotor connected.
36. Connect a spare wire between terminal "L" (left) to any G (GND). You should hear your brake relay (1) click, very shortly followed by your left relay (2). When you remove the L-G connection, left relay (2) should immediately click back, followed by brake relay (1) about 3 seconds later.
37. Connect the spare wire between terminal "R" (right) to any G (GND). You should hear your brake relay (1) click, very shortly followed by your right relay (3). When you remove the R-G connection, right relay (3) should immediately click back, followed by brake relay (1) about 3 seconds later.

Built

Here it is, built. I removed some of the unused space space on the LHS because it fits neater under the azimuth meter. The 7812 voltage regulator hangs off the bottom left. It is a little vulnerable there but allows easy addition of a heat sink if required - the 7812 can get hotter than you expect, as it is essentially acting as a resistor dropping your 30V to 12V, arguably wasting more power than the rest of the circuit added together. I found a very small 10k meter calibration pot (set to approx midpoint for the required 5k for 1mA FSD), there is space for a larger pot (over the wire). The terminal connectors are labelled:

• 7 = Terminal 7 (azimuth pot RHS)
• 3 = Terminal 3 (azimuth pot LHS)
• M = Meter PWM (0-5V "analogWrite()")
• G = Ground
• 5 = 5V from Arduino (to top of front-panel pot)
• G = another Ground
• R = Right button (pull to ground)
• B = Brake button
• L = Left button
• C = Calibration pot (0-5V analog in. The front-panel CalPot needs 5V, GND, and the middle connection to this "C")
• D = Debug (pull to ground to DISABLE - use the CalPot switch here if you have one, otherwise tie to a spare GND)
• X = Transformer (Xformer) AC in (low-V side of the smaller transformer, or one side of the the bulb. Other transformer/bulb terminal goes to any "G"

• Arduino (pins below board, 8 bent to fit)
• Upward Arduino-style sockets for shield stacking (but beware pin bending may be required!)
• Relay module (pins above board, then connectors across, down through board to socket below board). Alternatively you may prefer to run a ribbon cable from these to your relay board, depending on the space / chosen layout in your rotor controller box
• L+R LEDs (powered when the L+R relays are). Don't forget a suitable series resistor!
• A status LED (Red+Green) assumed to be common cathode but could be easily re-wired for common anode (Program Pin 11 to provide 5V)

Physical installation

+++ TODO: physical placement, USB port
+++ TODO: OTHER connection details (relays etc)
+++ TODO: include CW / CCW / status LEDs
+++ TODO: include meter calibration

Here it is in place in the bottom of the CDE case, connected to the Arduino and my relay module (both below my vero shield). The front panel will be at the bottom of this picture, with the meter on the left, the switches on the right. A hole is cut for the USB port in the LHS of the case, and mounting holes are drilled for proper mounting bolts but the boards are held in place with cable-ties until I get a chance to obtain the appropriate hardware.

Credit: rigpix

Parts list

(^*optional)

Software

I wrote my own rotor control software (+++ WORK IN PROGRESS +++).

I initially wanted to be compatible with Rotor-EZ, just because that's what the "other guys at the club" use/like, but after a bit of research, realised there are a number of other rotor control protocols out there, and Rotor-EZ's is not exactly the cleanest, most "complete", or the easiest to implement. There's also no really good reason why I should feel any loyalty to Rotor-EZ's protocol in particular, as long as I can control it nicely from some software on my desktop/laptop (EG anything that uses hamlib, most dx-cluster software).

I'd love to implement many protocols, in some neat multi-protocol-compatible way, which may or may not be practical, but in the meantime, some combination of Yaesu / EasyComm looks easier and cleaner than Rotor-EZ's slightly awkward handling of "AP1xxx<CR>" vs "AP1xxx;".

Honourable mention / shout-out to K3NG / Radio Artisan, and the Arduino Rotator Computer Interface blog post). I DID stumble across this project early in my research, but for some reason dismissed it on the mistaken understanding that it wasn't compatible with Hy-Gain/CDE rotors, only Yaesu ones (yaesu-rotator-computer-serial-interface in the URL?) or home-built ones, and/or was going to need a digital display or something. It turns out it could control my relays, can do Azi without Elevation, it's probably capable of doing everything I needed except my X = (Y-YZ) ÷ (Y+Z-2YZ) algebra. It could do a sort of adequate job of just measuring the voltage on one side of the AziPot, or, to be honest, I could probably have added my algebra into the K3NG code, and submitted it back for others to appreciate too. If I had realised this earlier in my software development lifecycle, I would probably have just written a rotator_pins_va3nnw.h, rotator_features_va3nnw.h etc. The K3NG / Radio Artisan code was really useful as a protocol reference for Yaesu / EasyComm protocols though, and also adds some nice "backslash commands" which I may borrow.

Most of what I have learned about Rotor protocols, I have learned from:

Commands

[ Sortable - click column headers to sort by command / response / etc ]

This stuff is maintained by Nick Waterman - Email Me