Model 177
Technical Manual
Section 4
Ludlum Measurements, Inc.
Page 4-2
October 2018
Connector:
Series "C" connector (Series BNC and MHV connectors are
also available). The connector is provided on the front of the instrument
for connection to a detector.
RESET Button:
This button, when depressed, provides a rapid means of
driving the meter needle to zero.
FAST-SLOW RESPONSE Toggle Switch:
When in the
FAST
position, this
switch provides 90% of full-scale meter deflection in 2.2 seconds. With
this switch in the
SLOW
position, 90% of full-scale meter deflection takes
22 seconds. If quick needle response and maximum deviation are desired,
the
FAST
position should be used. For slow response and damped meter
movement, the
SLOW
position should be used.
BAT TEST Button:
When this button is depressed, the meter displays the
battery status. A sufficiently charged battery is indicated when the meter
needle is on or within the
BAT TEST
range.
HV TEST Button:
When this button is depressed, the meter displays the
detector high voltage.
ALARM TEST Button:
When this button is depressed, the meter displays
the alarm calibration set point.
ALARM SET:
used to adjust the alarm calibration set point. Note the
locking knob below the control.
Back Panel
9 VDC INPUT:
Input for external 9 Vdc.
Data:
a 9-pin type “D” data plug with connections as follows:
PIN 1:
Battery terminal. This is a direct connection and does
not go through the front panel
ON
-
OFF
switch. Use to parallel
the battery.
PIN 2:
Unregulated supply from approximately 6 volts, battery
only at 8.7 volts with wall transformer plugged in. Limit
current drain to 50 milliamperes.
