A project that enables the use of the Icom AH4 autotuner with the Elecraft K3 and KX3 radios.
Edit -- March 2021: Greetings from the future! Many people have got in contact with me or my Dad asking for more information about this project over the ~7 years since it was created (if you contacted me and I didn't see the message/did not respond, I apologize!). Although it's a little late, I'm uploading all the files I have relating to the k3-ah4 interface so hopefully others can reproduce it without needing to rely on me checking my GitHub messages infrequently.
One note is that this project switches RS232 lines in and out of circuit with an analog switch, which definitely does not comply with the RS232 standard. The project worked great in the state I'm uploading it in, but it wouldn't pass a compliance test. As with all my work, use at your own risk, and have fun!
Schem. and board files are Eagle format. There's a free version of Eagle available to download if you don't own a copy already.
Ben