Gary, lock functions are done with the function button plus atten or function
plus preamp. There is also a demo mode on there which, if you get in to it, you
can't do anything. In this mode there are dolphins showing swimming on the
display. I forget how to get out of it but it says in the manual. Its got
something to do with the way you turn the thing on and off.
Tom
Tom Brennan KD5VIJ, CCC-A/SLP
web page http://titan.sfasu.edu/~g_brennantg/sonicpage.html