HP 8712C, User Manual, Page: 366 / 559

I
Front/Rear Panel
Connectors
AUX INPUT
EXT REF IN
EXT TRIG
IN/OUT
LIMIT TEST
‘ITL IN/OUT
This rear panel female BNC connector is for low frequency
(dc to approximately 360 Hz), low voltage measurements.
This input is calibrated for inputs up to
V, but will
accept signals up to V. See “Making Measurements with
the Auxiliary Input” in Chapter 3 for more information.
This rear panel female BNC connector accepts a
10 MHz signal from an external time base
reference. The nominal input impedance is 50
This rear panel female BNC connector allows external
triggering of a sweep. When the TTL level is pulled high, a
sweep is triggered. When the TTL level is pulled to ground,
the sweep is inhibited. This is an open-collector signal
which you can drive low, but must not drive high, since the
analyzer also drives it.
This rear panel female BNC connector provides a
bidirectional open-collector TTL high signal. The output
goes high when the limit test passes. The output goes low if
the limit test fails. This is an open-collector signal which you
can drive low, but must not drive high, since the analyzer
also drives it.
N O T E
Limit tasting can be set independently on each of the two measurement channels. If both
measurement channels are being used, and the limit test is ON for both channels, both measurement
channels must pass for the output to go high. See the following table.
8-5