As I and many others have learned, with ICOM it best to use an external relay(buffer relay) to key your amp. Well with most amplifiers anyway, there are a FEW exceptions that are LOW VOLTAGE/CURRENT. Maybe a few amplifier manuf might decide to put in an option for ICOM , that is a relay to key the amp relay inside the amp? 73's.. Larry...CU in the pileups for VP8..N2LH