c) The
SENSITIVITY
Switch. Using this button will toggle the
sensitivity of the receiver between a low and a high state.
That is, this switch controls the receiver’s overall sensitivi-
ty to the signal produced by the 902 transmitter. The LED
indicator above this switch monitors what the present
sensitivity mode of the receiver is. (NOTE: This switch
does NOT control the sensitivity of the receiver while in
“locate mass” mode.)
d) The
HI
Indicator. This LED indicates the present sensitivity
of the 902 receiver when in normal tracing mode. The
indicator will be lit to correspond to a state of high sensi-
tivity. Likewise, the LED will be darkened in the low
sensitivity mode.
e) The
LOCATE MASS
Switch and Indicator. Pressing this
switch so that the LED indicator directly above it illumi-
nates changes the 902 receiver from a line tracer to a
metallic mass locator. Examples of buried masses that the
receiver is able to find in this mode are valve caps and
manhole covers. Using the instrument in this mode
disables normal receiving functions.
f) The
SIGNAL LEVEL
Control. This knob is the most impor-
tant control on the 902 receiver from an operating stand-
point. While in tracing mode, use this knob to gradually
adjust the sensitivity of the receiver to the transmitted
signal. When tracing in “peak” mode, use this control to
set the point of maximum signal on the response meter;
in “null” mode, use it to adjust the width of the signal null.
Model 902 Pipe & Cable Locator
5