Ken WR7D added Elecraft KH1 support to the SOTACAT firmware in the 2026-01-11 version.
Since the KH1 has one jack with two functions (the ACC accessory CAT control serial port function, and the KEY keyer port function), it is a bit more limited in value compared to using a SOTACAT with a KX device. Still, you can use a SOTACAT with the KH1 to:
- Send an Alert, internet-free, (and then use RBHhole)
- Send a Spot, internet-free
- Click-to-Pounce (only when internet is available): see recent spots on your mobile device - clicking one tunes your VFO to that frequency.
- And other SOTACAT functions
The Alert is probably the most useful for a KH1 because you can do it on-summit in situations where an arrival time and summit ID aren’t known ahead of time: and then use RBNhole for spotting as you QSY. All without internet, and without sticking to a plan.
The SOTACAT can send Alerts and Spots internet free by directly synthesizing special FT8 messages that are picked up by about 130 monitoring skimmers running CWSL_Digi, SparkSDR, or other SOTAMAT compatible software. The SOTACAT teaches the KX and KH1 radios to generate the FT8 commands by transmitting the radio’s CW and rapidly changing the VFO oscillator. This method allows the radio to transmit (not receive) FSK (frequency shift keying) signals used by protocols such as FT8, FT4, RTTY, etc. without using audio.
While SOTACAT supports CW keyer memories on KX radios, it doesn’t on the KH1 (yet: but it is possible and Ken is considering it).
Software Developers: It uses the new FOnn; API in the latest KH1 firmware announced by Wayne N6KR (Elecraft). The source is available on Github.
Thank-you to WR7D: this was his first Github Pull Request and ESP32 submission. Looking forward to additional KH1 features from Ken! Thank-you to @n6kr Wayne (Elecraft) for adding the new FOnn; command to the firmware and allowing the open source community to do FSK!
73 de AB6D - Brian