Guys, I decided to try again and request that anybody with a schematic diagram for an ICOM IC-A5 please contact me. I have a problem with mating it to an intercom system. It will only transmit when the intercom unit is turned off. It would appear that the carrier wave is sent but without any modulation. Bill Clapp, didn't you have a sinilar problem a while ago? Regards Dene Collett KR2SRT builder South africa Whisper assembler See: www.whisperaircraft.com mailto: av...@telkomsa.net