For an explanation of the "input" frequency you see listed, Most 2 way radio traffic you hear from your scanner, either from your Fire Depeartment, Police, EMS, whatever, normally goes through a repeater. This allows the relatively low power mobile units in the patrol car, ambulance, etc to be able to talk to each other and not be out of range.
A repeater is just what it says it is. It's simply a radio transmitter and reciever tied together. The reciever part, will RECIEVE a transmission from Patrol Car #1 on the South side of town for example. Patrol Car #1 is TRANSMITTING on that input frequency that is listed. You WON'T be able to hear them unless they're fairly close to you. Ok, back to the scenario..
Patrol Car #1 will transmit on this input frequency to access the repeater. The repeater, then RE-TRANSMITS (or repeats) the transmission on the OUTPUT frequency. The repeater is usually higher in power than the mobiles, and, since the repeater will re-transmit on the same frequency from EVERY Patrol Car, you can hear all the police action, on ONE frequency. Regardless of how far away each car is from your scanner.
It's confusing at first, belive me, but once you get in the hang of scanning, and get more experienced, you'll learn. Repeaters are a way of life for 2 meter and 70 cm band amateur operators. If you want to program in the input, it's up to you, but don't expect to hear much unless you're somewhat in the vicinity of a Patrol Car or Fire Truck, then you'll only be hearing them, and not everyone else like you would by programming in the first listed frequency, or repeater output.
Welcome to RadioReference also, and I love the avatar!!
