On 11/21/2019 9:00 AM, John P Lloyd via Groups.Io wrote:
Putting it on an antenna has the same result with the hum.John -
So are you saying the hum is still present on the dummy load? Or only when used on an antenna?
73, Bob W9RAN
PS: There is not a separate PTT line as in most radios, the N-75 detects the change in voltage that occurs when the mic PTT switch is closed. To key the radio w/o the mic you'll need a 4-circuit TRRS plug - short the sleeve and first ring together.