Hi All,
New guy here trying to dust off some old skills that I've let atrophy away. I'm looking for some direction to build a modern version of circuit that's been around a while. In the aviation world a lot of small airports have a lighting system that can be turn on by a pilot by tuning a specific frequency in the air band (118-137Mhz am 25kHz spacing) and transmitting 3 one second bursts of carrier. Some of the old stuff I've looked at used relays and cascading charging of capacitors to so this (yeah really old). I'd like to do a 21st century version of this using a PIC based controller but am looking for some direction on the RF part of this. I was thinking a programmable oscillator running at the desired freq feeding a mixer with some notch filter and threshold detector circuit on the output of mixer that the PIC will monitor. Is this still the way it's still done (my rf knowledge is from the 80's) or is there some one chip wonder that simplifies all this?
New guy here trying to dust off some old skills that I've let atrophy away. I'm looking for some direction to build a modern version of circuit that's been around a while. In the aviation world a lot of small airports have a lighting system that can be turn on by a pilot by tuning a specific frequency in the air band (118-137Mhz am 25kHz spacing) and transmitting 3 one second bursts of carrier. Some of the old stuff I've looked at used relays and cascading charging of capacitors to so this (yeah really old). I'd like to do a 21st century version of this using a PIC based controller but am looking for some direction on the RF part of this. I was thinking a programmable oscillator running at the desired freq feeding a mixer with some notch filter and threshold detector circuit on the output of mixer that the PIC will monitor. Is this still the way it's still done (my rf knowledge is from the 80's) or is there some one chip wonder that simplifies all this?