Got 2 radios - (5SHPn's) and one of the ARC-DA5830SD1's in today from Baltic Networks. So far received 2 orders from them and they seem to be a dependable source. Got a couple of rubber ducks and some adapters to round out the package for a garage to house link so I can do some playing around with the OS and a few other things. Ordered and received a Yeasu 5500 AZ/EL rotor with a FoxDelta ST-2 PC interface (used). Had to make the cables between the rotor control box & rotor. All tested out very nicely. FoxDelta is a serial-port driven interface that can also control the rotor via front panel push-buttons. The 2 line LCD shows programmed AZ and EL, as well as current AZ/EL. Protocol for commanding it seems to be very straightforward and quite simple. Character codes followed by text or integer values, sent via serial port. Current position can be read the same way. Calibrated the unit and put it through full rotation testing via Hyperterminal <g>. Commanding and controlling the rotor should be fairly easy - going to start an application to do a predictable pattern of scanning for measuring the antenna radiation patterns. Bart - we traded a basic outline on the scan setup, but we'll need to come up with however you want to coordinate the position control with the measurement recording. Do you want to have the position sent to the test equipment, output the test equipment values to the PC to be recorded with the position, or something else? I don't know that I need the info right this second, but we can start thinking about it in the background. Sunday will be my first day to play with it, but barring Murphy it shouldn't take THAT long (famous last words..) Cheers, Rob