Introduction

to the

Oscilloscope

Agilent Technologies 54622D 100MHz Scope

Sometimes you want to see how signals change with time

Electrical signals are invisible, unless you know how to look at them.

The Oscilloscope provides us glasses

2 Analog Channels Displayed

Horizontal Sweep (Time Base)

Soft keys

Vertical Amplitude

Trigger Controls

Run Control

16 Input Channels of Digital Signals

Operation Controls

Floppy Disk

How do I turn it on?

Wait for a while as it goes through a self test.

Analog vs. Digital

Sometimes you want to know the analog details, other times you just want to know the logical interpretation.

2 analog channels

16 digital channels

We'll Start with the Analog Section

See something quick and simple

1) Reset all settings to default. Hit Save/Recall, then Default Setup.

2) Connect probe(s) to Probe Comp, then hit Autoscale

Do this whenever settings get messed up

Push down on the top part to expose the little hook.

Experiment with Vertical and Horizontal controls.

Adjust slowly to observe effect.

2 Analog Channels Displayed

What's this triggering stuff?

You want a repetitive signal to appear to stand still.

• Normal Triggering Runs only if it sees a signal that can trigger it. If trigger level isn't set right—you see nothing!

• Auto TriggeringFree runs. Good for seeing if something is happening.

• Auto Level TriggeringRuns so long as there is a signal.If trigger level isn't set right—the scope adjusts it for you! (may not be such a good thing – there is no free lunch)

Start with Auto (free running) triggering, then go to Normal

Press Mode/Coupling keyCycle through modes with first Softkey

Auto triggering

Normal triggering

Notes on Autoscale

Autoscale works good on signals like this:

Not so good on signals like this:

This is noise

The signal you're looking for is

actually here, but it's way off scale

If you hit autoscale on a signal like the latter, you might get something like this:

Recovering from AutoscaleEither:Hit Autoscale, then undo Autoscale

or

Set gain to reasonable value (say 10 V per division)

Keep line visible

Move trigger levelto reasonable value

1 volt per division

Fiddle knobs till you see what you want.

200 microseconds per division

trigger voltage

0 volts(ground)becsuae of the little symbol in the margin, NOT because it's the bottom of the trace.

Saving Display to Disk

Insert floppy disk

Press Utility key

Set up Print Configuration with SoftkeysFormat tiff (bmp can be used also)Print to: disk

Press Quick Print (Saved on disk with file name QFILE nn )

Remember … when things get all messed up!

Start over by resetting all settings to default.Hit Save/Recall, then Default Setup.

If things still aren't working POWER DOWN and restart the COMPUTER.

You've got the basics

For additional details and capabilities, go to the manual. There should be some lying around, if not ask your instructor.

Digital Addendum

Digital Section

Enable one or both digital inputs

Disable analog display by double clicking buttons 1, 2.

After you're sure that you seeing something

Set trigger to a digital channel (probably).

What you trigger on depends on what you're looking for. If you're counting, trigger on D7.