Introduction to the Oscilloscope

1. Introduction to the Oscilloscope Agilent Technologies 54622D 100MHz Scope

2. Sometimes you want to see how signals change with time Electrical signals are invisible, unless you know how to look at them.

3. The Oscilloscope provides us glasses

4. 2 Analog Channels Displayed

5. Horizontal Sweep (Time Base)

6. Soft keys

7. Vertical Amplitude

8. Triggering (Sweep) Controls

9. Run Control Stop, Continuous, Single sweep

10. 16 Input Channels of Digital Signals 16 of these !

11. Operation Controls

12. Floppy Disk

14. How do I turn it on? Wait for a while as it goes through a self test.

15. 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

16. We'll Start with the Analog Section

17. See something quick and simple! • Reset all settings to default. Hit Save/Recall, then Default Setup. • 2) Connect probe(s) to Probe Comp Do this whenever settings get messed up

18. Here is what the probes look like Push down on the top part to expose the little hook.

19. Experiment with Vertical and Horizontal controls. Adjust slowly to observe effect.

20. 2 Analog Channels Displayed

21. 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 Triggering • Free runs. Good for seeing if something is happening. • Auto Level Triggering • Runs 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)

22. Begin with Auto (free running) triggering, then go to Normal Press Mode/Coupling key Cycle through modes with first Softkey

23. Auto triggering (always see trace) Normal triggering (see trace when trigger Condition is met)

24. Notes on Autoscale(I don’t recommend using Autoscale!) Autoscale may work good on signals like this: But it is not so good on signals like this!: If you hit autoscale on a signal like the latter, you might get something like this: The signal you're looking for is actually here, but it's way off scale This is noise

25. Recovering from Autoscale Either: Hit Autoscale, then undo Autoscale or Set gain to reasonable value (say 10 V per division) Keep line visible Move trigger level to reasonable value

26. Fiddle knobs till you see what you want. 200 microseconds per division 1 volt per division trigger voltage 0 volts (ground) because of the little symbol in the margin, NOT because it's the bottom of the trace!

28. Saving Display to Disk • Insert floppy disk • Press Utility key • Set up Print Configuration with Softkeys • Format  tiff (bmp can be used also) • Print to:  disk • Press Quick Print (Saved on disk with file name QFILE nn )

29. 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.

31. Now you are an expert! For additional details and capabilities, go to the manual. There should be some lying around, if not ask your instructor.

32. Digital Addendum

33. Using the Digital Section

34. Enable one or both digital inputs Disable analog display by double clicking buttons 1, 2.

35. After you're sure that you are 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. Why?