86 6000 Series Oscilloscope User’s Guide
2 Front-Panel Controls
•50Ohm mode mat ches 50-ohm cables commonly used in
making high frequency measurements, and 50-ohm active
probes. This impedance matching gives you the most
accurate measurements since reflections are minimized
along the signal path. When 50Ohm is select ed, “50Ω” is
illuminated on the front panel next to the channel position
knob. The oscilloscope automatically switches to 1 M Ohm
mode to prevent possible damage if AC coupling is
selected.
•1MOhm mode is for use with many passive probes and for
general-purpose measurements. The higher impedance
minimizes the loading effect of the oscilloscope on the
circuit under test.
4Press the BW Limit softkey to turn on bandwidth limiting.
Pressing the BW Limit softkey turns the bandwidth limit on or
off for the selected channel. When bandwidth limit is on, the
maximum bandwidth for the channel is approximately
25 MHz on the 300 MHz, 500 MHz, and 1 GHz bandwidth
oscilloscope models and approximately 20MHz for the
100 MHz bandwidth oscilloscope models. For waveforms
with frequencies below this, turning bandwidth limit on
removes unwanted high frequency noise from the waveform.
The bandwidth limit also limits the trigger signal path of any
channel that has BW Limit turned on.
When BW Limit is selected, “BW” is illuminated on the front
panel next to the channel position knob ( ).
5Press the Invert softkey to invert the selected channel.
When Invert is selected, the voltage values of the displayed
waveform are inverted. Invert affects how a channel is
displayed, but does not affect triggering. If the oscilloscope is
set to trigger on a rising edge, it remains set to trigger on a
same edge (triggers at the same point on the waveform) after
the channel is inverted.
Inverting a channel will also change the result of any
function selected in the Math menu or any measurement.