I now have an interface circuit with software that allows the VFO to be band-switched with a rotary switch.
Using a 74HC147 priority encoder, nine HF bands can be stored and switched in (1.8, 3.5, 7.0 MHz, etc.)
Please add $5.00 to the kit price. Rotary
switch kit includes instructions, 74HC147, software to accomplish
the switching, and the nine resistors and capacitors needed to
pull up the 74HC147 inputs and filter the nine rotary switch
positions for switch bounce.
I am assuming you have your own
rotary switch (single-pole, 9 positions), as many users have
these built-in to an older transmitter,etc. You will also need
a small piece of perf-board to mount the included socket for
the 74HC147.
