I acquired an older IC-2710H recently, and find that it doesn't seem to want to transmit DTMF tones on the 440MHz band. It works o.k. on 2 meters and I can hear the tones going out. But when I use the same procedure (Function, DTMF, press and hold PTT, then press numbers on the mic keyboard), nothing happens. I wonder what's wrong?? 73 - George, N9EJS