Boonton 9240 RF Voltmeter - Manual (Page 14)

Boonton 9240 Series RF Voltmeter
• Simple Instrument Setup and Operation. The front panel conductive rubber keypad provides
access to menus which control instrument operation. The MENU key selects channel, setup and
diagnostic menus. The <SENSOR> key selects sensor related function. The <AVG> key selects
filter time averaging controls. Setting the filter time to zero will select the auto-filter mode. This
selects an appropriate filter time without operator intervention. The <REF LEVEL> key is used
for making relative measurements in dBr or percent. The values for these parameters are displayed
and can be adjusted by using the arrow and enter keys.
• One key press operations. To provide for ease of use operation of the instrument functions that
are used often, they can be performed with a single push of a button. Common operations such as
Zeroing the channel calibration and setting a Reference Level can be done simply by pressing the
<Zero> and <REF Level> key respectively.
Zero – When measuring low level signals it is important to zero the channel prior to measuring
the signal. When the Active Channel is measuring levels below approximately -50 dBm,
depressing the <Zero> key will use the measured reading as the zero offset. This allows for fast
zeroing of the channel so that the needed measurement can be performed faster.
The Zero sub-menu can be displayed by first pressing the Menu key followed by the <Zero> key.
From there the user chooses the channel to perform a zeroing operation on.
REF Level – Often relative measurements are required especially when measuring system gains
and losses. One key press of the <Ref Level> key makes this job easier and faster to perform.
Simply connect the active channel’s sensor to the input signal of the system under test. Press the
<Ref Level> key and the reference level is set! Next, connect the sensor to the system output and
read the gain or loss directly from the reference level measurement.
The REF Level sub-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.
• Chart Recorder Output. A 0 to 10 volt dc output, proportional to the measurement values is
available for application to a chart recorder. The Recorder Output is selectable to track either
channel 1, channel 2 or the active channel. The Chart Recorder Output is a BNC connector located
on the rear panel.
• Flexible Remote Control. All instrument functions except power on/off can be controlled remotely
via the standard GPIB bus interface or RS232 connection. Setup of interface parameters is menu
driven; front panel indicators keep the user informed of bus activity. Remote control programming
is performed using industry-standard SCPI programming syntax. The 9230 emulation mode is
provided for users that prefer back compatibility with legacy Boonton products such as the 9230
series line of RF Voltmeters.
• Stored Configurations. For applications in which the same instrument configurations are used
repeatedly, up to 10 complete setups can be stored and recalled.
• HIGH/LOW Limit Alarms. The ALARM function provides a means to monitor the power level in
each channel independently. When the ALARM is "ON" (enabled) the level on the channel is
continuously compared with the HI and LO Limit values. The 9240 sets indicator flags (up and
down arrows) on the channel display when the limit values are exceeded. There are 4 status bits in
the Operation Condition register byte which, when unmasked, can be used to request service over
the IEEE-488 interface bus when the selected alarm condition occurs. Note that choosing
overlapping limit conditions is not an error, but may result in confusing alarm indications.
General Information
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