ETS-Lindgren 3816-2 LISN - Manual (Page 15)

www.ets-lindgren.com Installation and Application 15
L INE S ELECT S WITCH
Select the line to be monitored by the three-position selector switch. The line not
selected is internally terminated into 50 ohms. When using the remote (center)
position, connect the monitored line to the 9-pin connector on the rear panel.
Control signals are low-level 5 volt DC.
 To monitor Line L1, apply +5VDC to pin 1 of the 9-pin connector.
 To monitor L2, apply +5VDC to pin 3.
 Should +5VDC be applied to both pins, the first pin to receive the
control signal will be selected.
 As with manual selection, the line not selected is terminated into 50 Ω.
 Pin 2 of the 9-pin connector is control common.
Although the unit is provided with resistors to
help bleed off high voltage transients, connect
the input and output connectors to their proper
power lines and loads before connecting the
monitor port to the measurement instrument.
Otherwise, you may damage the mixers or
attenuators of the test instrumentation due to
power surges or transients.
Switching between the two lines will not generate transients. Remove the power
source first when disconnecting power.