Boonton 9240 RF Voltmeter - Manual (Page 30)

Boonton 9240 Series RF Voltmeter
Table 3-1 Operating Controls, Indicators and Connections
(continued)
Reference #
Front Rear Nomenclature Function
12 <REF Level> Key Often relative measurements are required especially when measuring system gains
and losses. One key press of the Ref/Level key makes this easier and faster to
perform. Simply connect the active channel’s probe to the input signal of the system
under test. Press the Ref/Level key and the reference level is set! Next connect the
probe to the system output and read the gain or loss directly from the reference level
measurement.
The REF Level menu can be displayed by first pressing the <Menu> key followed
by the <REF Level> key. From there the user may LOAD or SET the reference
level on either channel.
13 Recorder Provides a DC voltage proportional to the measured values for use by an external
recorder.
14 RS232 9-pin D-sub connector for connecting the voltmeter to the remote control Serial
Bus. Communication parameters can be configured through the <SETUP <RS232>
menu.
15 GPIB 24-pin GPIB (IEEE-488) connector for connecting the voltmeter to the remote
control General Purpose Instrument Bus. GPIB parameters can be configured
through the <SETUP <IEEE> menu.
16 AC Line Input A multi-function power input module is used to house the AC line input, main
power switch, and safety fuse. The module accepts a standard AC line cord,
included with the voltmeter. The power switch is used to shut off main instrument
power. The safety fuse may also be accessed once the line cord is removed. The
instrument’s power supply accepts 90 to 264VAC, so no line voltage selection
switch is necessary.
Caution Replace fuse only with specified type and rating:
0.5 A-T (time delay type), 250VAC
Getting Started
3-4