My 601 has recently developed an intermittent problem transmitting, which today led to me being unable to call up a marina on my fixed set, but when I used my handheld M1 Euro I got through with no problem.....
Reception on the 601 is fine, and when I held down the PTT it was showing Tx on the top of the screen.
This happened a while back, but then last time I was out the set worked fine. Perhaps Jon can set me straight?....
Incidentally, it came without the coastguard MMSIs programmed in, so that kept me busy for a while