DETECTOR OF UNDERGROUND SERVICE LINES Russian patent published in 2003 - IPC

FIELD: instrumentation, facilities for contact-free determination of route, depth of lying and points of damage of underground and hidden service lines such as cables or pipe-lines. SUBSTANCE: generator of tone pulses includes master stage, manipulator, buffer stage, power amplifier, unit matching with line, measurement circuit and power supply unit. Receiver of detector incorporates magnetic antenna, narrow-band tunable filter of concentrated selection, output amplifier, acoustic transducer, rejection filter, wide-band low-frequency amplifier, low-frequency filter, acoustic indicator, pointer-type indicator, power supply unit, indicator of discharge of power supply battery, amplitude detector, delay line, subtractor, integrator, divider, former of reference voltage, comparator and key. EFFECT: increased noise immunity and measurement reliability under conditions of heavy noise of natural and artificial origin. 3 dwg