HP 8920A, User Manual

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S:\HP892XX\USRGUIDE\manual\connkeys.fb
Chapter 24, Connector, Key, and Knob Descriptions
Connector Descriptions
15. Parallel Data In/Out
• You can designate these pins as outputs or inputs with the
I/O CONFIG
field of
the RADIO INTERFACE screen. Pins designated as inputs are pulled high by the
Test Set. Output level and input logic thresholds are set by the logic voltage (pin 9).
• Pin 19 is LSB, Pin 34 is MSB.
• High level output is Logic Voltage through a 3.16 k
Ω
pull-up resistor.
Output current sink (TTL low, voltage
≤
1.5 V) is 6 mA minimum, 16 mA typical
Input data logic threshold is (Logic Voltage
−
0.7 V)
×
0.34
The default Logic Voltage is 5.1 V.
• Read back on the data bus is accomplished by setting all data lines to the high state
and then having the user pull appropriate data lines low according to the data to be
read back.
16. No Connection.
See Also
Chapter 16, "Radio Interface Screen"
.
RF IN/OUT
This Type-N connection is used to output signals from the RF Generator and to
input RF signals.
CAUTION: Overpower Damage — Refer to the Test Set’s front panel for maximum input power
level. Exceeding this level can cause permanent instrument damage.
If the RF power at the RF IN/OUT port exceeds allowable limits, a loud warning
signal sounds and a message appears at the top of the screen. If this occurs,
disconnect the RF power, press [MEAS RESET], and allow the Test Set to cool
off for approximately 2 minutes before making any other measurements on this
port.
Operating Considerations
This port must be used when measuring TX (RF) Power.
Signals
≤
200 mWatts can be input to the ANT IN connector for all RF
measurements except TX Power.
This port can be selected in the TX TEST, DUPLEX TEST, RF ANALYZER, or
SPECTRUM ANALYZER screens.
See Also
"Displaying Measurements" on page 57
.