I struggled for hours to get iFTx working with my DR-891 and FT-891. It was a learning curve but I finally got it running. The DR-891 and the cable hookups are straightforward. The biggest challenge for me was getting the settings right on the iPhone and the radio.
How to configure iFTx (FT8/FT4 iOS app) for use with the Digirig DR-891 and Yaesu FT-891.
HARDWARE REQUIRED
Apple iPhone with USB-C port (iPhone 15/16/etc.). Older iPhones (must be iOS 15.0 or later) will need a USB-C adapter. Also works with Apple iPad per info from the seller at the App Store.
Digirig DR-891 with included transceiver cables for the Yaesu FT-891 transceiver
Shielded USB-C extension cable with ferrite chokes (connects between DR-891 and iPhone).
Yaesu FT-891 transceiver
SOFTWARE REQUIRED
iFTx iOS app, available through the Apple App Store (Price $1.99)
Connect a shielded USB-C/USB-C cable with ferrites between the DR-891 USB-C port and the iPhone or iPad USB-C port. Note: if you intend to charge the iPhone/iPad simultaneously while using the DR-891, you may need a suitable USB-C splitter or powered USB-C hub and a charging cable for the iOS device. In general, these devices do not get very good consumer ratings nor have I tried any of them.
iFTx SETUP INSTRUCTIONS
Follow the instructions in the iFTx documentation to setup the settings.
iPhone SETUP INSTRUCTIONS
When connecting the USB-C cable between the DR-891 to the iPhone or iPad, you may receive a popup asking if the connected device is a headset or a USB device. Select USB device.
Turn on the iPhone/iPad microphone for the iFTx app. Go to Settings / Privacy & Security / Microphone. Locate the iFTx app in the list. Turn on the microphone for the app.
Turn off the ringer
Turn the volume all the way down, then turn it up just one click. This affects the ALC on the FT-891. You will adjust the volume setting later. in conjunction with a Menu setting in the FT-891.
YAESU FT-891 SETTINGS
Note: iFTx does not provide CAT control so you must manually change frequencies on the FT-891. If you change modes from FT8 to FT4 or vice-versa, you must manually change frequencies on the FT-891. In addition, you must manually change the band setting in the iFTx settings menu on your iPhone/iPad.
FT-891 MENU SETTINGS
05-06 CAT RATE: 38400 bps
08-01 DATA MODE: OTHERS
08-02 PSK TONE: 1500
08-03 OTHER DISP: 1500
08-04 OTHER SHIFT: 1500
08-05 DATA LCUT FREQ: 300
08-07 DATA HCUT FREQ: 3000
08-09 DATA IN SELECT: Rear
08-10 DATA PTT SELECT: DAKY
08-11 DATA OUT LEVEL: 50
08-12 DATA BFO: USB
16-03 HF PWR: 5 (Note: start with the 5W setting until everything is working)
16-10 DATA MIC GAIN: 5 (Note: the radio’s default setting is 50 and we want a starting value of 5.
FT-891 FUNCTION MENU SETTINGS (accessed with short clicks of the F key)
NOTE: KEEP ALL FUNCTION MENU SETTINGS OFF EXCEPT THE FOLLOWING:
FUNC-1/WDH: 3000 HZ
FUNC-2/MTR: ALC (though you will also use PO and SWR, too)
FUNC-2/AGC: AUTO
FREQUENCY & MODE SETTINGS
Set FT-891 to a FT8 frequency using the BAND menu (short press) or a preset memory
Set iFTx band to the same band as the radio is on. Go to settings.
Set FT-891 to DATA mode (D-U on the display) using BAND menu (long press)
OBSERVATIONS
The radio’s Data Mic Gain setting (Menu 16-10) works in conjunction with the iPhone/iPad volume level to control the FT-891’s ALC level. The goal is to have the right combination of Data Mic Gain and iPhone/iPad volume that (during transmit) will simultaneously produce an ALC level of zero and the same power output as set in FT-891 menu 16-03. Any SWR above 1:1 can affect ALC and actual output power. I set my FT-891’s Menu 16-10 to a value of 5 and adjust my iPhone’s volume control buttons 1 click at a time up or down to adjust the radio’s ALC level during transmit. I use the MTR button located on the radio’s FUNCTION-2 screen to sequentially monitor power (PO), ALC level (ALC) and SWR until I get the ALC down to zero and also get the same power output as set in Menu 16-03. If you change bands or even 100 kHz on the same band, check the levels on the ALC, power and SWR to make sure they are still good.
RFI will almost certainly be an issue unless you put ferrites on each end of every cable that connects to the radio. Even doing so, RFI can be an issue if you use a tuner to compensate for an antenna that is non-resonant on the operating frequency. Be sure to carefully read Troubleshooting Digital Modes, particularly the section "Sticky Transmission, Errors on Transmission).
Setting up the Digirig DR-891 is the easiest part of the whole process. Getting the settings right on your radio and iPhone/iPad is the challenging part. Though you might get lucky, don’t expect “Plug & Play” as there is a lot of complexity in setting up and reliably operating any data mode.
I tried the iFTx installation on an old iPhone 6S Plus with iOS 15.8.3 using an Apple Lightning-to-USB-C adapter cable. I could not get iFTx to decode except with acoustic coupling from the radio’s speaker, nor to transmit (I did not try acoustic coupling and VOX, which are supposed to work). My buddy AE9Q tried the same thing with an Apple iPhone 12 with an adapter and also could not get it to transmit. Until someone can verify that they were able to get an older iPhone (14 or earlier) to work with the phone cabled to the DR-891, I recommend using an iPhone 15 or higher which use the USB-C connector.
Sorry I didn’t respond sooner. The Holidays were crazy.
I was able to just plug in my iPhone to the DigiRig and it just worked for me.
But I had already configured the FT-891 for WSJT-X on a Windows 10 laptop using most of the settings you described in your write up.
Your write up is awesome. It will definitely help the next person.