T A K I N G M E A S U R E M E N T S
5 Taking Measurements
This section helps you learn how to measure, analyze, and record signals using the BB60, utilizing built-in
features such as markers, record/playback, and channel power.
Measuring Frequency and Amplitude 5.1
Using Markers 5.1.1
The BB60 software has several tools for identifying a signal’s frequency and amplitude. The easiest to use
is the marker. There are 6 markers available, each with its own reference.
To activate and place a marker you can left click inside the graticule or press the Peak Search button on
the marker controls to place the marker on the current trace peak and activate it simultaneously. Once a
marker is active the frequency and amplitude readout of the marker is located in the top right of the
graticule. The marker’s accuracy is dependent on the span and RBW. Narrower spans and RBWs have
higher marker accuracy. The amplitude accuracy is NOT dependent on the vertical dB/div, since the
I/Q data is linear in voltage and has much higher resolution than is displayed. The marker may be re-
placed at any time by clicking the graticule or by using the left and right arrows to shift the marker one
sample point to the left or right.
Using the Delta Marker 5.1.2
To measure differences or changes in frequency and/or amplitude you can use the Delta markers. To
use the delta markers you must first create a reference point. With a marker active click the Delta control
panel button. This places a reference location on the graticule. Now you can move the marker elsewhere
on the graticule and the marker readings will report the difference between the marker and the reference.
Measuring Low Level Signals 5.1.3
To measure low-level signals, there are a few tricks to getting accurate readings. First, set the
internal electronic attenuator to 0 dB (click the Atten button). Then, set your reference level to -50
dBm or lower. This internally selects the highest sensitivity settings. Using an external time base
and narrow span (1 KHz or less) should give you the best results. Video averaging may be required
for a stable amplitude reading.
Saving Sessions 5.2
The playback toolbar allows you to record and replay a continuous session up to the file size set in
Preferences
Max Save File Size. The length in time of the session will be dependent on the average sweep
speed of the session and trace length. Sessions files are named based on the current time and date. This
naming scheme ensures no files are overwritten and relieves you of determining file names when you
really want to capture a signal immediately. Pressing record on the playback tool bar causes the software
to immediately begin recording. All playback files are saved in your “My Documents” folder with the
.bbr file extension.
When replaying a saved session, all functionality of the software remains. You can place markers, activate
min/max/average traces as well as view the recording using persistence and spectrogram views. In
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