Hi Elma, All,

I migrated from ICOM hence need your help.

Anyone here able to guide how i might interface SunSDR2 DX with my remote ICOM AH-4?

Hi,
The AH-3/4 can be used with non Icom radios of any sort including the SunSDR 2 DX by using this simple interface

pacificcoastsail.com/PCSC_working/Blog/BOAT%20RESOURCE%20LIST%20VIP/mods_dk%20-%20ICOM%20-%20AH-4.htm

It works fine for me with my SunSDR2 DX . I am also using an LDG AT-200 Pro II autotuner on the other HF antenna socket for my other antenna so both are available as required.

73 gd DX

Hi 9V1PL

I'm looking into buying a SunSDR2 DX myself and I'm trying to find out how to connect it to my tuner.
My tuner (LDG Z-11 Pro) uses the 4-pin connector today with my Icom radio, so I think your solution will work.

How did you connect it to the radio exactly?

The SunSDR2 DX diagram for the ATU connector I have found is this:
eesdr.com/images/Document/SunSDR2_DX/ATU_pinout.JPG

Did you use pin 7 to control the white wire (directly or with a relay) in addidion to VCC and GND?

Hi LA5OUA,

Like yourself I kept wondering how, using our traditional Icom cabling concept and idea got me really puzzled.
Not to mention I am new and also not technical at all, just an operator level!

Then I realized my LDG AT-1KPro2 is an Auto tuner with (RF sensing). Here are my solutions (QRP and QRO):
QRP:
SunSDR2 DX <==> LDG AT-1KPro2 <==> SWR PWR Meter <==> EFHW UNUN (Just coax, removed all custom control cables)

1. Click Tune on EESDRv2 or v3(Software) on PC, sends a tone from SunSDR2 DX (Increase Tune PWR to 40% if Tuner not picking up PWR)
2. LDG AT-1KPro2 would auto tune (If set to auto mode)
3. Press and hold LDG AT-1KPro2 Tune Button (If set to semi-auto mode)
Doesn't matter what band is selected on SunSDR2 DX, all band works.

QRO:
SunSDR2 DX <==> ACOM 1010 <==> LDG AT-1KPro2 <==> SWR PWR Meter <==> EFHW UNUN
SunSDR2 DX <==> ACOM 1010 (Additional keying cable - DB15 to RCA)

1. Put Amp to STBY (Bypass) or Click on PA on EESDRv2 or v3 to OFF it.
2. Click Tune on EESDRv2 or v3(Software), sends a tone from SunSDR2 DX
3. LDG AT-1KPro2 would auto tune (If set to auto mode)
4. Press and hold LDG AT-1KPro2 Tune Button (If set to semi-auto mode)
5. Reduce PWR on SunSDR2 DX (You might get PWR spike on 1st TX)
6. Put Amp OPER and ensure to Click on PA on EESDRv2 or v3 to switch it ON***
Doesn't matter what band is selected on SunSDR2 DX, all band works.

Feel free let us know if you need further clarification. I asked a lot and at times felt like an idiot. Still got my DXCC lol!

Thank you Terry.

Wondering if you have come across any other methods without using a switch?

Hi again 9V1PL
Thank you for a good description of your setup.
So you use your tuner only in Auto-mode without any control signal from the radio?
I wonder if it would be possible to use some of the wires/pins from the ATU connector to trigger the "Start tuning" operation. Maybe in combination with pins from the DB15 connector?
I aim to use this setup remotely, so physical buttons is not a good option.

Terry, G4POP, do you know more about this?

Hi LA5OUA,
No problem.
I also had all these thoughts prior to my cross over as well, i understand your thoughts.

I was very happy and surprised, there's no need for any other connector to trigger the "start tuning". Just set LDG to full auto and TX, the tuner will tune immediately.

I then saw my IC-PAC rotting away on my desk!!! lol!

Hi,

I have SunSDR2 DX for about a two weeks, migrating also from ICOM stuff (old but well filtered IC-756, which was enough for me during boring minimum of the solar cycle). I have FB-33 tribander and for rest of bands I've been using cca 84 m horizontal loop, at cca 6 m height around our garden, feeded by symetrical line (realized as insulated spacers between rest of loop wire). Just behind my shack wall is located balun 1:1 and old AH-3 tuner. This antenna can be easily tuned on any HF band except of the 160m and despite of its low height performs acceptably good and much better than trapped multiband verticals above poor ground.
Last Friday before ARRL DX CW I decided that I must solve how to comfortably tune AH-3 without any other actions (for first tests I used old IC-756 set to minimal power with dummy load as power supply and 'tune button' to AH-3 connected to SunSDR2). Fortunatelly, thanks to Enzo IW7DMH esp32 TCI library iw7dmh.jimdofree.com/sunsdr2-pro-pages/tci-esp32s-arduino-libraries/ was easy to attach one NPN transistor as open collector driver to GPIO port of the ESP32 devboard. In the demo project in the mentioned TCI library I added simple initialisation of the GPIO pin and in the TUNE event handler I've added three lines with pulling GPIO high, wait a second and pull it back to low state. Transistor is connected to white wire of the AH-3 cable, of course together with 12V DC supply, to pull this line low to start tuning procedure.
The tune level should be set between 5 to 10W output power, outside this interval tuner won't work, Tuning procedure is automatically started when TUNE button is pressed, progress is clearly visible at SWR indicator. When finished, I simply click on TUNE button again and voila, let's go transmit. It is quite simple action, but in future it might be improved to more automated function, because TUNE function in EESDR could be controlled through TCI directly from esp32 based on for example detection of the band change and/or detection of bad SWR..
But I am afraid (as I know myself) that there is non-zero posibility, that my 'half hour engineering project' leave as is, laying in cable chaos behind my table, because it simply works enough for my needs,

I'll share photos, schematic and code later, if anyone are interested.

73!

Hi, sounds like a vy interesting project. Please share schmatic, code and pictures if possible

I have set up automatic tuning for my SPE with a TCI bridge based off Enzo's library with more extensions. This is a PoE ESP32 board that discovers the EESDR client machine and then automatically turns the SPE on when EESDR2/3 is turned on. In this particular application, It will automatically read the frequency of the EESDR TX VFO and set the SPE to that band over CAT (using Kenwood's CAT protocol). On top of that, I have a python script running on a PC that sets the subband mid-frequency of the EESDR over TCI, then talks to the SPE amplifier over serial/USB and turns on the TUNE mode, then activates EESDR2/3 tuning carrier over TCI, and then monitors the SWR and tuning process for completion. When it is completed, it deactivates the tuning carrier and moves to the next frequency and repeats this until the whole band is tuned. I have a video here that shows how that works:-



I imagine something similar can be done for the AH-4 but I am not sure if it is possible to read the SWR that the AH-4 is seeing, and/or to know when tuning is complete. Presumably this should be possible. Additionally, Enzo's library only speaks Kenwood CAT but the AH-4 might require CI-V CAT?

AH-3 and AH-4 external ATU has very simple protocol without any data communication between TRX and ATU. There is only 4 wires connection, 12V power supply, GND, one input for initiating of tuning and one output with pull-up resistor (presence of about 10 kOhm between this output and 12V is used for detection of presense ot the external ATU by ICOM TRX), which signalize tuning process or unsuccesful tuning resp. pass-thru after it (continuously ground the pin during tuning, then off in succesfull tune or several cyclic on-off when unsuccesfull and pass-thru). When input is triggered down longer than about 700 msec, tuning start, when input is triggered about 70 msec, tuner is switched to pass-thru state. ATU has power measurement on input and switch over to pass-thru state to protect input attenuator when input is over cca 10 W. Frequency of input signal is measured and relay states are stored in non-volatile memory for particular frequency intervals, therefore repeated tune procedure is much faster than initial one for the same antenna. So, the minimalistic variant of ATU control is simply transmit signal between 5 to 10 W and pull its input for something over 700 msec down to GND. Then we can react multiple way - in my case I just wait a little bit and watch the power/swr meter, when swr falls down and do not change any more, then I know that tuning is done and I can just tap second time to TUNE button at EESDR. As I mentioned before, it was a quick and dirty solution just few hours before ARRL DX contest .Another (and yes, more correct and elegant) solution is to detect state of ATU state output and stop TUNE transmit by TCI command, yet another solution might be detect SWR by TCI and stop tune transmit when SWR stabilize somewhere at low value.
I plan develop it more in combination of antenna switch control to upgrade my existing automatic antenna switch.
danielwee could you share your source for inspiration? I am interested especially in seeking of the EESDR host address.

Sure - happy to share it. I'm assuming you are more keen on the ESP32 code? The whole tuning thing really depends on a number of components on my side. The ESP32's primary job is to:-
1. detect that a TCI client (EESDR) has connected to the radio, and determine it's IP
2. turn the SPE amplifier on automatically if the client is turned on, and turn the SPE off when the client is turned off
3. translate the SPE's CAT frequency polling (Kenwood CAT) to TCI and translate the client's response back to Kenwood CAT and send to the SPE via serial port
4. host a telnet server for control and information

For the purpose of using this with the AH-4, there does not appear to be any CAT signals involved since the AH-4 always detects the carrier frequency, unlike the SPE's ATU which allows you to pre-tune a particular band/sub-band and will pre-set the tuning based on frequency read over CAT. For the AH-4 there is no need for this. Hence, what is really better for the AH-4 is to built whatever translation circuitry is needed to make the AH-4 appear like an ATU-100 to EESDR. Alternatively, and even simpler, all you need is to get the tune signal from the ATU port on the radio and use that to trigger tuning on the AH-4. You could potentially add some controller to automate the starting and/or stopping of the tuning process.

danielwee of course, it would be best option to have chance to make protocol translator between SunSDR and AH, unfortunatelly there is not published protocol for ATU-100, as far as i know EE guys won´t like to share it with public..

That's true, but might not be too hard to reverse engineer. If all we need is a trigger for the ATU, I think that's very easy to find.

So guys, here is schematic of my quick and dirty Icom tuner interface:



I have used tiny chinese DC/DC buck inverter from 12V power supply to 5V because ESP32 devkit uses LDO for 3,3V which is little bit hot when supplied directly from 12V.

On software side I just use example ptoject from IW7DMH esp32 TCI library with those one minute done modifications:
1. defined GPIO pin for ATU triggering output, initialize GPIO and for sure hold it down - modify file TciDemo as shown below, lines with yellow marker:



2. In Events file just modify event handler for Tune this way (yellow marker):



You have to connect to ESP32 devkit by serial console at 115200 Bd, type help and follow setup (wlan ssid, wlan passwd, host IP, port..) Set parameters are stored in NVRAM, no necessary to set it up again. Then It should work, don´t forget to set Tune power somewhere between 5 to 10 W.