Proper calibration of an oscilloscope is extremely important. This is because calibration of an oscilloscope helps to maintain job integrity. It is vital that oscilloscopes can read data accurately. If an oscilloscope is out-of-tolerance, then the likelihood of false measurement is high. When false measurements occur, undesired consequences will be faced such as unhappy customers, extensive downtime and costly repairs.
To prevent false measurement, an oscilloscope must be calibrated routinely. Think of it as an oil change. Would you skip your routine oil change for your car? No. Most of us know that not changing our oil leads to even most costly repairs. By keeping your car maintained you are reducing the unnecessary costs. This same principle should be used towards oscilloscopes.
PARTS TO CALIBRATE
When sending your oscilloscope in for calibration, it is essential to ensure the following parts are being calibrated.
- Switching Channels
- Range and Accuracy of Deflection
- Bandwidth – Pulse response and rise time
- Accuracy of time base, including delay, magnification and jitter
- Trigger functions
- X-axis accuracy of deflection
- X-Y phasing
INTERNAL CALIBRATION SIGNALS
CURSORS AND MEASUREMENT READOUTS
OSCILLOSCOPE CALIBRATION INTERVALS
To ensure you are calibrating your oscilloscope when needed, a calibration interval should be created. Most oscilloscope manufacturers will recommend specific time frames of when to calibrate an oscilloscope. This recommendation is a great starting point for creating an oscilloscope calibration interval; however, other factors must be taken into consideration as well. Consider the following when creating a calibration interval:
- The required accuracy of the job vs. the oscilloscope’ accuracy.
- The impact out-of-tolerance will have on the specific job and measurements needed.
- The oscilloscope’s performance history and how frequently it is used.