HP 8590 E-Series User Manual page 36

4 GATE TRIGGER INPUT ('ITL) accepts a TTL signal which acts as the gate trigger. In
edge mode, the trigger event (positive or negative edge) initiates a gate delay. In level
mode, the gate trigger input signal opens and closes the gate directly: TTL high sets the
gate on; TTL low sets the gate off. When this input is unconnected, TTL is set high. For
Option 105 only.
5 EVENT CNTR INPUT ('ITL) accepts a TTL signal and counts the negative pulses (a
falling edge followed by a rising edge) that occur during the gate time interval. 0ption
E02 only. This input is used to test for digital radio signal errors when using the
HP 11758T Digital Radio Test System.
6 GATE OUTPUT (TI'L) provides a TTL signal which indicates gate status when the when
the gate is in edge trigger mode. A high TTL signal indicates the gate is on; a low TTL
signal indicates the gate is off. GATE OUTPUT is not active in level mode. For 0ption
105 only,
7 EARPHONE connector provides a connection for an earphone jack instead of using the
internal speaker. For Option 102, 103, or 110 only.
8 INTERVAL CNTR INPUT ('ITL) accepts a TTL signal. It identifies negative pulses (a
falling edge followed by a rising edge) and measures the accumulated time that a pulse is
low during the gate time interval. Option E02 only. This input is used to test for digital
radio signal errors when using the HP 11758T Digital Radio Test System.
SWEEP + TUNE OUTPUT provides a voltage ramp that is proportional to the spectrum
9
analyzer span (0 to 10 V) plus the tuning voltage of the LO. For Option 009 only.
10 LO OUT provides the output of the first LO, which is proportional to the frequency that
the spectrum analyzer is tuned to. For Option 009 or 010 only.
11 EXT REF IN accepts an external frequency source to provide the 10 MHz, -2 to
+ 10 dBm frequency reference used by the spectrum analyzer. Not availablefor HP
8590L with Option 713 or HP 8592L with
12 10 MHz REF OUTPUT provides a 10 MHz, 0 dBm minimum, time-based reference signal.
Not available for HP 8590L with Option 713 or HP 8592L with Option 713.
13
14 MONITOR OUTPUT drives an external monitor with a signal that has a 15.7 kHz
horizontal synchronizing rate. It can also be switched to provide an NTSC format output
which is compatible with VHS video recorders or a PAL format which is compatible with
15 Power input is the input for the line power source. Make sure that the line-power
source outlet has a protective ground contact.
16 AUX INTERFACE provides a nine-pin "D" subminiature connector for control of external
devices. Refer to specifications and characteristics in your calibration guide for a more
detailed description.
2-6 Getting Started
713.