[moved] help with understanding oscope concepts

[twainerm]

Hello,
I am just learning how to use oscilloscope. Concept of triggering is confusing to me as I am unable to visualize what exactly is happening.
Say, I have a clock signal at some freq and voltage level is 0v to 3v. Clock signal is a continuous signal. I want to see when there is a spike in the clock signal and I set trigger to 5v. How does clock signal look on scope now?

I read online before posting here and everyone says "trigger freezes signal" and "horizontal sweep". What does this mean? what is a "horizontal sweep"?

Please can someone explain it to me in simple english. :-(

Thank you for your time.
Mark

 

[retrogear]

horizontal sweep is what moves the trace across the display on your scope. how fast it travels is set by the hor. sweep control rated in time/division
the trigger sets the vertical (voltage) point on the waveform when the sweep starts.

 

[betwixt]

If you want to trigger the trace to capture a spike you ideally need a storage oscilloscope so it can show the spike itself and not just what happens afterwards.
The best you can do without storage is to set the trigger level to a point just higher than the highest normal voltage in the signal, this will unlock the trace so it free-runs and probably makes no sense - but then you select single sweep mode (sometimes called "one shot" mode) which makes the trace stop at the end of it's current cycle. It will then stop (no trace) and trigger again only when the spike occurs.

Brian.

 

[Warpspeed]

What kind of oscilloscope do you have there Mark ?