ARDUINO CAT INTERFACE FOR ANTENNA SWITCH BY ON7EQ

An ideal tool for connecting your IC-706 or IC-7000 to more than one antenna and having them switched automatically.   You could as well use it to drive a 5 bands BPF ... or  develop an antenna tuning unit, a magnetic loop variable condenser stepper motor drive etc ...
This sketch will readout on a 2x 16 characters LCD display the frequency of any ICOM transceiver by reading the CAT line (the device acting as a listener only, the transceiver is set to 'CAT TRANSCEIVE' mode to broadcast data) and switch 5 + 1 antenna's  (or band pass filters... ) according to band.
Up to five digital outputs are to be interfaced with relays, the sixth position is 'no relay energized'.  CAT activity will be displayed in the top row, on the right side (a small 'c' will show up when valid CAT data is received).  I used 9k6 as my SPE power amplifier runs at 9k6 as well. The ARDUINO board is simply put in parallel with it.
The matrix can be programmed with 2 push-buttons (scroll left or right), the values are permanently stored in EEPROM after a small delay, once the choice is definitive (this to avoid too many write cycles to EEPROM). When the new setting is memorized, a small 'M' will briefly show up on the second line at right.  The switching combination can be different for RX and TX  (reading the PTT line, it will select the right antenna).  In program mode, you have to depress a push button which indicates this is the 'TX' antenna.   In TX mode, no antenna can be changed / programmed with the scroll buttons.

All the settings programmed in the matrix can be cleared if you depress button scroll buttons at startup / reboot.
Read More for arduino code or visit http://www.qsl.net/on7eq/projects/arduino_ant_matrix.htm


Reference: ( http://www.qsl.net/on7eq/projects/arduino_ant_matrix.htm )