The MAC-51Bx was discontinued by Schonstedt and is no longer available for purchase. This is a great tool as it handled dual-purpose functions. It was a Pipe/Cable Locator and a Magnetic Locator. If you're looking for a Pipe/Cable Locator and a Magnetic Locator we suggest that you purchase the XTpc and the GA-52 separately. While suggesting buying two tools instead of one was not the goal of the manufacturer, manufacturing the MAC-51Bx was not the direction they decided to take.

The MAC-51Bx is the most cost-effective, all-purpose locating system on the market. It consists of a magnetic locator, similar to the most popular GA-52Cx model, and a null-over-target pipe and cable locator capable of locating on two frequencies: 571Hz and 82.5kHz.

In the LO and HI modes, the receivers audio signal provides a sharp null when its tip is directly over the target. In the MAG mode (no transmitter required) the audio signal peaks when the receiver's tip is over the target. You can trace the 571 Hz LF signal conductively applied to any continuous metal conductor up to 4000 feet.

The receiver's on-the-fly mode-changing feature lets you locate a complete break using the LO mode, and then continue on to trace beyond the break in the HI mode, or trace a metal pipe joined with non-conductive gaskets.

The MAC-51Bx by simultaneously transmitting 82.5 kHz (HF) and 571 Hz (LF) signals lets you select and compare received audio signals from both frequencies along with magnetic information without having to return to the transmitter