Dog Collar Radio
How dog tracking collars works?
a dog tracking collars is made of two parts: a collar which sends a radio signal, and a tracker which receives the signal and show the location of the dog. a general describtion of it is here: http://www.gundogsupply.com/how-dog-tracking-collars-work.html
I want to make a circuit doing similar thing but don’t know how it works.
Any idea?
You may have misunderstood how the dog collars work. The location of the dog is not determined precisely, but the general direction and distance is determined.
The direction is determined by comparing the signals received by two antennae simultaneously. The phase difference (time delay) between the two signals can be used to determine the general direction, turning the receiver until both signals are equal would mean the receiver is pointed directly at the transmitter. A third receiveing antenna could be used to help “triangulate” the direction more precisely.
Distance can be determined by the strength of the received signal. The signal strength gets weaker with distance.
Describing how to build a radio transmitter and receiver would take more room than I have here, but there are a lot of different integrated circuits that do the job with minimal external components, and the spec sheets for these integrated circuits usually contain example circuits that are used for testing.
FBHW Producer Joe Dog Collar Trivia Part 1