An oscilloscope is used to view a voltage waveform on a screen. An electron beam
is generated in the cathode ray tube, directed at the back of the screen, and swept in time
along the X-Axis. A voltage applied to the scope probes is amplified and applied
to a pair of horizontal metal plates through which the electron beam passes. This
voltage deflects the beam in the vertical direction (Y-Axis). The sweep in the
electron beam combined with vertical deflection results in the appearance of a
waveform on the screen of the scope.
The scope has two probes: one for Channel 1 and one for Channel 2.
The probes are very expensive (approx. $200 each), so please be careful with them.
Each channel has a vertical placement knob which moves the waveform for that channel up and
down. Each channel also has a knob which selects the vertical scale of the waveform
in terms of volts per division. Divisions are the visible grid lines on the oscilloscope
screen. The
knob which sets the horizontal scale in time per division controls both channels. The
majority of all measurements made in this lab can be performed automatically with the HP54600
scope.
To see the waveform, press Auto-scale.
The Auto-scale button will be used more than any other on the scope. When you
want to capture a waveform on the screen, the first thing to think of is Auto-scale.
This takes the waveform at the input and
displays it so that the entire peak-to-peak voltage is displayed as well as several
periods. To measure voltage, push the button marked voltage which
is located to the right of the screen near the top of the front panel. This will bring up a menu
at the bottom of the screen, listing available voltage measurements. The first choice is to
select either channel 1 or 2 for measurement. After that, you may select: Peak to Peak
voltage (
), average voltage (
), or rms voltage (
). By pressing
the corresponding softkeys, you will automatically get the selected measurement. For more
choices, press the softkey labeled Next Menu. The next menu will allow you to select:
, 
, 
,
, 
, 
or 
. Time measurements can be obtained by
pressing the Time button (located next to the voltage button).
This will give you the following menu options: Frequency,
Period, Duty Cycle, +Width, -Width, Rise Time, Fall Time, Delay and Phase Difference.
This last command, Phase Difference, is useful for computing the difference in phase
between waveforms on channels 1 and 2.