FT-991A With An External Antenna Tuner

I’ve been making a ton of QSOs with my Yaesu FT-991A from my home station, mostly on FT8. I have an end fed half wave antenna and use an antenna tuner to get as good a match as possible. I’ve had an LDG AT-200Pro external automatic antenna tuner (LDG now sells the AT-200ProII) for years. I have always been happy with it. Even though the FT-991A has an internal antenna tuner I’ve just stuck with the old tried and true.

Since most of my operating lately has been on FT8 the external antenna tuner works great. The radio transmits for 15 seconds. This is plenty of time for the tuner to get things sorted out. WSJT-X even has a Tune button to key up the radio, which is also convenient.

When I try to operate SSB things are a bit more problematic. Ideally I need a few seconds of a solid signal to let the AT-200Pro do its work. But some voice doesn’t cut it and I’m not a fan of whistling into the mic. Other radios I’ve used in the past, including my old Kenwood TS-680S, had a convenient button for this scenario. Press the Send/Rec button in CW mode and it sends a continuous carrier.

The FT-991A has a number of buttons on its front panel. But the vast majority of its controls and settings are accessible only via its touchscreen menu system. I had never found an equivalent button on the panel or in the menu, until now.

The solution I found may be obvious to many/most operators. I thought I’d write about it here to ensure I never forget it. To key up the transmitter do the following:

  • Place the radio into CW mode
  • Lower your output power
  • Ensure CW break in (BK-IN) is ON
  • Ensure the CW keyer (KEYER) is OFF

This is the same configuration one would use if you were to plug in a straight key into the radio. You can find this on page 78 of the manual.

I have Bencher Paddles plugged into the radio, but that doesn’t matter. Now, press and hold the dit paddle on your keyer. As long as you hold it in place your radio will transmit a carrier. Now the external antenna tuner has more than enough time to get SWR as close to 1:1 as possible.

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    1. Jerry,

      The AT-200ProII antenna tuner just sits inline on the transmission line. So in other words, the radio connects to the tuner and the tuner connects to the antenna. There’s no need for extra cabling between the radio and tuner. The tuner senses any transmitted signal and acts accordingly.

      Robert KA5WSS

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