I was wondering if you could tell me how I can make a 216-220 mhz transmitter. I am wanting to use the transmitter on a dog collar so it has to be pretty compact. I have already made a reciever using a pro-94 dual trunking scanner from Radio Shack, attatched to a homemade yagi antenna I built using 1/2inch pvc for the boom; coax, and pieces of tape measure for the elements. The antenna works with existing collars I have, which work on 216, 217, 218, and 220 mhz. Now if I could just figure out how to make on of these transmitters I could save a lot of money, each collar is about $150. I found a kit at Ramsey Electronics that was used to track model rockets but it only reached 1/4 mile, and it was the wrong frequency. I need this transmitter to put out a signal that can be picked up at a mile or more if possible. Any help you can give me on this would be greatly appreciated. SLC1414