I would like Ideas On how one could build a device to attach to the ground wire of burried cables (such as the telephone company does) to detect the burried cables Location. was thinking of loading the wire with a 440 Mz transmitter through a match box and using a 440 reciever to find the cable. but I am not sure this will work.
There are two different methods used for this. One is a simple metal detector. This is what is used for finding buried cables before digging. You do not have to have a power source in the cable to find it. The other type is an inductive pick up which pulses an amplified votage, then is sent to either an audible source or a visual one. This type of circuit also does not require you to send a signal through it as it is used to sense a signal that is already there. I do not have a metal detector schematic handy, but I am sure they are all over the web. I do have an AC Wire locator schematic, which I have attached. For the coil in this circuit, you can use the type that has a suction cup and attaches to a telephone. These are common in the phone bug projects. This might not be exactly what you are looking for, but might give you a start and hopefully some ideas on making your device.
MP
AC_Wire_Locator.zip
MP
AC_Wire_Locator.zip
