@w2aew;
"To test this hypothesis on your scope, setup the 100k or 1MHz square wave and make the rise time measurement. Without changing the horizontal controls, simply change the square wave frequency on the FG down to 100Hz. You should still have a rising edge on the screen, and it should still be reading the same fast rise time. This is the true rise time. "
Exactly! Same rising edge & same rise time.
As usual, thank you very much for your detailed explanation.
Regards.
@w2aew;
"To test this hypothesis on your scope, setup the 100k or 1MHz square wave and make the rise time measurement. Without changing the horizontal controls, simply change the square wave frequency on the FG down to 100Hz. You should still have a rising edge on the screen, and it should still be reading the same fast rise time. This is the true rise time. "
Exactly! Same rising edge & same rise time.
As usual, thank you very much for your detailed explanation.
Regards.
It is very unfortunate that your scope LIES to you at the lower sweep speeds. Better digital scopes will at LEAST tell you that they have "low resolution" or "insufficient sample rate" for a given measurement in these types of cases. It's good that you now know about this characteristic of your scope.
I helped teach a class on the basics of oscilloscopes to the New Jersey Antique Radio Club. This club is dedicated to the restoration and preservation of antique radios - mainly from the golden age of broadcasting. The class was geared entirely around analog scopes, since that's the type of scope that these guys would most likely come across or have access to for their radio restoration projects. We affectionately called the class "Scopes for Dopes", and it was a great success.
Fortunately, the session was videotaped. We had two projectors going - one with presentation slides, and one with a video camera feed that was focused on a few scopes on a table for demonstration.
To make it easier to navigate this long video - over 2 hours long, here is a list of time-stamps and the topics that begin at those timestamps. Using this "table of contents", you can easily move the youtube player location to the topic of interest.
0:00:00 Opening and Agenda
0:02:50 Brief History of Oscilloscopes – with Al Klase
0:15:00 Start of Basics of Oscilloscopes – with Alan Wolke
0:19:00 Basic Block Diagram of an Oscilloscope
0:19:50 Oscilloscope / Display Overview
0:23:00 Display Section Functions and Controls
0:28:10 Vertical Section Description
0:33:17 Vertical Scale / Coupling Controls, Input Impedance
0:38:04 Vertical Mode Controls
0:48:05 In-circuit Example of using two traces on the oscilloscope
0:52:41 Horizontal Section Description
0:53:48 Horizontal Sweep Types & Controls
1:10:15 Triggering (Synchronization) Section Description
1:13:19 Trigger Source, Mode and Coupling Controls
1:19:56 Trigger Level and Slope Controls
1:23:29 Introduction to Oscilloscope Probes
1:31:45 1X and 10X Passive Probes
1:34:00 10X Probe Compensation and Use Considerations
1:48:48 XY Mode of Operation
2:00:12 Front Panel Control Layout
2:02:20 Pop Quiz!
2:03:00 Wrap Up: Oscilloscope adds Intuitive Feel to circuit operation
2:04:45 Questions and Answers
2:13:35 Brief History of Oscilloscope Tubes
Also, if you are interested, I have a couple of other oscilloscope videos on my YouTube channel:
https://www.youtube.com/w2aew
...including a tutorial on 1X and 10X probes...
Great video!
Thanks really good tutorials! Also i found this online oscilloscope emulator: http://www.virtual-oscilloscope.com/simulation.html
Hope that helps someone
Thanks really good tutorials! Also i found this online oscilloscope emulator: http://www.virtual-oscilloscope.com/simulation.html
Hope that helps someone
Great tool, thanks for posting!
Watching this has been on my 'to-do' list. Finally put in the time today to watch the whole thing. Very informative and enjoyable. Thanks so much for posting the video!