Inductive wire loop sensing

I was trying to find some information about how the 'invisble pet fences' worked. I know I need a signal running through the wire boundary and coils to pick this up. My idea was to have a vehicle enclosed in the wire loop and be able to detect when it was close to the wire boundary. I have been able to find very little info on circuitry to drive a signal through the wire. I am guessing I need some sort of pulsed signal going through the wire and the pickup coil will need to be tuned accordingly. Any info or links to some info would be awesome! Thanks, Jacob

this is similar to this
https://www.electro-tech-online.com/threads/radio-frequency-circuit-design.20260/

Thanks alot for the link. That confirms my thoughts on the pulsed signal through the loop antenna, and the formula for the resonant frequency of the LC circuit were extremely helpful! -jacob

Hi, did you build your Robot's electronic fence ?

Richard

billericayboy said:

Hi, did you build your Robot's electronic fence ?

Richard

Click to expand...

hi Richard,
Its 2 years old.

what circiut did you use and how does it connect to the robot I2c ??

Any circuit diagrams or photos would be a great assistance.

Thanks

Richard

never tried anything