This determines the highest frequency signal you can measure. For general hobbyist work, aim for at least 50–100 MHz .
Professional refurbished units from manufacturers like Keysight are calibrated and often come with a warranty. Essential Pre-Purchase Tests buy used oscilloscope
Deeper memory allows you to capture longer time windows while maintaining a high sample rate, which is crucial for finding intermittent glitches. This determines the highest frequency signal you can measure
If buying locally, perform these checks to verify functionality: ensure it passes without error codes.
Buying a used oscilloscope can save you hundreds of dollars, but it requires careful testing to ensure you aren't inheriting someone else's "blown front end" or calibration nightmare.
Most modern digital oscilloscopes (DSOs) run a self-test on startup; ensure it passes without error codes.