I recently bought an old Icom IC-706 MKIIG for portable operation, so I wouldn’t have to pull my Yaesu FT450-D out of the shack when I wanted to radio from Delaware. It worked, but I didn’t realize how much I’d miss having an internal tuner, among other things.
So I sent it down the road and bought a gently used FT-991A, which I have used before and scratches the all-band, all-mode itch.
My goal was to build a portable setup that fits into a single Apache case, which I quickly realized was not possible with the 706. The 991A provides a single cable interface for audio, CAT, and PTT, which really simplifies portable digital operation. So I found a deal on a refurbished Lenovo ThinkPad tablet, which conveniently also fits in the case with the radio.
There is already a lot of info available regarding the digital settings for the 991A, and despite this being my second 991A setup adventure, I still had a few issues getting a signal from WSJT-X to the antenna. This seems very common. It is a lot of learning curve in a small package, and has the menu options to prove it (153 options, to be exact).
Configuration of the FT-991A for digital operation with WSJT-X can be broken into three parts: software, radio, and audio settings.
Software Configuration
Before connection the radio via USB, the Yaesu virtual com port drivers should be installed. Once the radio is connected, there will be two COM ports added, one that is used for CAT and one for RTS. Keying can also be done over PTT or VOX.
Radio tab:
- Serial Port: COM3
- Baud Rate: 4800
- Data Bit/Stop Bit/Handshake: Default
- PTT Method: RTS
- PTT Port: COM4
- Mode: USB
- Split Operation: None
Audio tab:
A big part of the appeal of the FT-991A is the built-in audio interface. With the drivers installed and radio connected via USB cable, there are two sound devices (microphone and speaker) marked USB AUDIO CODEC. Input is microphone, output is speaker. You’ll know you have the wrong audio device selected when you attempt to transmit via WSJT-X and the screams of the damned erupt from your PC speakers.
Radio Configuration
I performed a factory reset on the FT-991A when it arrived, so these are the menu options that were changed from their defaults.
- 031 CAT RATE: 4800bps – This can be any value as long as WSJT-X and radio configs match.
- 032 CAT TOT: 100msec
- 062 DATA MODE: OTHERS
- 066 DATA LCUT FREQ: OFF
- 068 DATA HCUT FREQ: OFF
- 070 DATA IN SELECT: REAR
- 071 DATA PTT SELECT: RTS
- 072 DATA PORT SELECT: USB
- 106 SSB MIC SELECT: REAR
- 108 SSB PTT SELECT: RTS
- 109 SSB PORT SELECT: USB
The SSB options are necessary because the software is using USB rather than USB-DATA. Otherwise the software will be able to PTT, but no audio will be transmitted. This is one of the more common issues I came across when researching the “radio keys up but no power out” problem.
Audio Configuration
At this point, WSJT-X should be able to change the frequency via CAT control and key up the radio. If done properly, there may even be something transmitted. A lot of operators will stop here and scream into the bands without adjusting input/output levels, as is tradition. If you notice your ALC meter go into the red during TX, you are one of these operators.
In the [F/M-LIST] menu, DT gain should be rolled back to about 10, and adjusted up from there. Otherwise distortion may occur.
The audio levels on the PC side are adjusted via the sound settings in the operating system. Input level via Microphone (USB AUDIO CODEC) should be adjusted to a level that maxes the receive meter in WSJT-X at around 60db.
Receive will probably still work if the audio level isn’t set properly, but transmit requires a little more finesse. It is very easy to send distorted audio by sending it too loud. On my Thinkpad, adjusting Speakers (USB AUDIO CODEC) to an output level of 10 is barely audible to the radio. An output level of 50 pushes the ALC into the red. A setting of 25 seems ideal.
Now that I have everything configured, I can throw this radio into an Apache case and forget about it until I go to Delaware for the weekend.