Chuck, I don't think you're right - the K3 'Key Out' is spec'd 200V @ 5A. The FL2100 'RY' relay control switches 12V @ 200mA only. 73 Tom G3OLB AE4CW wrote: >However, you will need an interface to key the amp from the K3 as the amp >keying voltage is not compatible with the K3. I used a simple 12V reed >relay powered from the K3 12V RCA jack.