Patrick
Another option and probably easier is to see the guy at the entrance who directs traffic and he will programme the devices for you. Its strange watching him do it. He takes the device upto the barrier's control box. Puts his ear to control box as he stops all noise listenning for something for about 10 seconds and then says its good. Everybody carries on working. And they work too now. I gave him a tip as it saved the time and energy going to AEA.
How's the golf?