101 Things you can do with a Scope + Oscillator

[thermionic]

edit: As suggestions are made, I will add them to the list. Scrolling down the thread will reveal who the suggestions are credited to.

Question: Let's say you have a modest, sweepable oscillator (that goes from, say 10Hz - 100k) and a 20MHz oscilloscope. The mind boggles at the amount of tests that you could perform.

How many procedures can you list?

You can:

1) Look at DC rails for ripple / noise

2) Measure frequency response by sweeping a tone and observing amplitude

3) Observe phase relationships between waveforms

4) Have various means of looking for distortion at your disposal, ranging from looking at the harmonics on a square wave, to using lissajous mode

5) See if there's any HF oscillation present in the MHz region

6) Test compressors / limiters

7) Tune a zobel network for transformer ring reduction

8) Determine total latency of A/D—DAW—D/A signal chains

9) Measure/observe transient response of RC, RL and RCL circuits. Same could be done on individual components such as charge/discharge characteristics of a capacitor.

10) Check how close the amplifier is to instability (square-wave response).

11) Check overload behaviour of amplifiers

12) Measure slew-rate

13) Check current limiting circuitry

14) Trim CMRR

15) Align + Bias analogue reel machines

16) Trim DC offset in output stages

17) Trim various output amplifier topologies for symmetrical clipping (Neve 283-types being a famous example)

18) Examine noise and calculate SN Ratio / Dynamic Range

Your turn. How many things can you list?

 

[Skylar]

7) tune a zobel network for transformer ring reduction

8) determine total latency of A/D—DAW—D/A signal chains

 

[sahib]

9) Measure/observe transient response of RC, RL and RCL circuits. Same could be done on individual components such as charge/discharge characteristics of a capacitor.

 

[leadbreath]

get some nice psychedelic looking waveforms/images on the scope display???

does this count??

 

[hobiesound]

get some nice psychedelic looking waveforms/images on the scope display???

does this count??

HELL YES!!!  ;D

 

[Samuel Groner]

You can see if there's any HF oscillation present in the MHz region.

And how close the amplifier is to instability (square-wave response).

* check overload behaviour of amplifiers
* measure slew-rate
* check current limiting circuitry
* trim CMRR

And much more which just doesn't want to come to my mind right know...

BTW, make sure to differentiate mHz (milli) and MHz (mega).

Samuel

 

[thermionic]

You can see if there's any HF oscillation present in the MHz region.

And how close the amplifier is to instability (square-wave response).

Samuel

This is something I wanted to get across in a recent discussion about whether a scope was absolutely essential (which prompted me to start this thread), as I had an EQ which would oscillate around 3MHz, but only slightly under very specific conditions, i.e. a specific combination of boost / cut. Without a scope, diagnosing this fault would've driven me crazy.

 

[thermionic]

It would actually be easier to list all the tests you can't undertake with a scope than list those you can...

Some more:

Align + Bias analogue reel machines

Trim DC offset in output stages

Trim various output amplifier topologies for symmetrical clipping (Neve 283-types being a famous example)