Heath Consultants Aqua-Scop - Manual (Page 10)

The push button “LISTEN” control switch should only be depressed
after the ground microphone has been firmly placed on a solid surface
and one to two seconds Sensor Settle Time elapsed. When using the
direct contact microphone, be certain that the tip is in firm contact with
the pipe, valve box, etc., before depressing the “LISTEN” control
switch.
B. Ground Microphone (Part No. 2916427)
(Figure 4)
1. General Specifications:
Construction: Acoustically suspended variable
reluctance sensor
Impedance: 380 Ohm DC resistance
Frequency
Response: 10 - 300 Hertz
Weight: Approximately 2 Lbs. 5 Oz.
(1049 grams)
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