Probe for trenchless guide instrument

A probe for a trenchless guide instrument comprising:

• a battery region and an electronic region adjacent to the battery region;
• an antenna;
• a control circuit board disposed inside the electronic region;
• at least one battery disposed inside the battery region;
• a first insulating pipe disposed inside the antenna and outside the at least one battery;
• a metal pipe connected to the first insulating pipe, and
• a second insulating pipe disposed inside the metal pipe,
• wherein,
• the at least one battery supplies power to the control circuit board;
• the first insulating pipe is disposed inside the battery region, and the antenna is disposed outside the first insulating pipe;
• the metal pipe and the second insulating pipe are disposed inside the electronic region,
• the control circuit board is disposed inside the second insulating pipe,
• the antenna further comprises a magnetic core, and a coil winds around the magnetic cores and one end of the coil is connected to the control circuit board;
• the magnetic core further comprises a plurality of magnetic core units, each magnetic core unit is made from magnetic material, the plurality of magnetic core units are positioned on a peripheral surface of the first insulating pipe, and are insulated from each other.