Pauly

It has been a long time since I took radio theory but if my memory serves me well dual conversion means that when your receiver 'receives' a signal on the channel it is tuned to it mixes the received signal with a set frequancy in the intermediate stage of the receiver (usually 455khz on am, don't remember what on fm) this process is called hetrodyning and it effectivly lowers the frequancy of the signal so it can be again mixed (hence dual conversion) down to a lower frequancy where the intelligance (in this case instructions for the servos) can be discriminated from other noise on the signal (ie:electrical interfearance from near by power lines etc.) and sent to the proper channel to drive the servo in the approiate direction and ammount of travel.

Hope this helps,
Sincerely Tom. aka Lomchevak.