The lost plane beeper/alarms are designed to look for incoming control signals from a transmitter on the same frequency as the receiver in the plane. If the alarm circuitry is powered, i.e. receiver battery is on, but senses an absence of incoming signals, the beeper starts sounding. One way to locate the plane is to intermittently turn the transmitter on and off and listen for a beeper going on and off.
It would seem that the same circuitry would help avoid a shootdown. The procedure would be to turn on the receiver to check the airways before you turn on your transmitter (e.g., before launch or before ground testing your equipment at the field). With the transmitter off, the beeper should sound. If it does not, that means that there are signal pulses coming into the receiver from some other transmitter. Silence would mean that you shouldn't turn on your transmitter. Does anyone use a lost-plane beeper in this mode? Of course, additional frequency control would be required to prevent someone else from turning on his same-channel transmitter after you are in the air. Dick -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Dr. Richard C. Williamson Phone: 781-981-7857 Room C-317 FAX: 781-981-0122 Lincoln Laboratory Email: [EMAIL PROTECTED] Massachusetts Institute of Technology 244 Wood Street Lexington, MA 02420-9108 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
