Are these radios programable via the front panel? There is a button marked program, that if held down for a few seconds will display a series of settings, but nothing can be modified. Going on what little information I could find on the net, I have tried momentarily shorting S1 to ground (does nothing) and shorting S2 to ground (brings up what I believe is the transmit/recieve frequency and will allow you to modify the value, but offers no way to store anything). Don't have a manual and can find no info on the net. Any help would be greatly appreciated.