Hi
I have a low-end cheap setup, mostly stuff from Banggood, with two cheap multimeters, a bench PSU kit that I just put together that I needs calibration, zener diodes, resistors (although no low-tolerance ones that I am aware of), some regulators like 7805, 7812, op-amps, laptops with supposedly 5v USB supplies, some of those cheap voltage measuring units (with LED displays) and some Arduino and ESP32 microcontrollers.
I don't have expensive (for me) Fluke multimeters or a high end oscilloscopes that get sent for factory calibration once a year. (Let's assume I don't have access to "reliable" stuff either).
What is likely to be my best approach to getting a "gold standard" reference that I can believe? Do I start at the 3.3v pin on an Arduino and treat it as gospel? Or does a zener diode likely give me a better reference than a linear regulator? Are multimeters generally better at either measuring current or voltage, (internally of course they are the same but we hope they used low-tolerance circuitry), and is it generally better to try to measure near the middle of a range rather than at extremes? (Maybe volts rather than millivolts, or KV).
Are there any algorithms for "successive refinement" of calibration in the case that your resistors are at best 10% accurate, etc.
Thanks
Peter
I have a low-end cheap setup, mostly stuff from Banggood, with two cheap multimeters, a bench PSU kit that I just put together that I needs calibration, zener diodes, resistors (although no low-tolerance ones that I am aware of), some regulators like 7805, 7812, op-amps, laptops with supposedly 5v USB supplies, some of those cheap voltage measuring units (with LED displays) and some Arduino and ESP32 microcontrollers.
I don't have expensive (for me) Fluke multimeters or a high end oscilloscopes that get sent for factory calibration once a year. (Let's assume I don't have access to "reliable" stuff either).
What is likely to be my best approach to getting a "gold standard" reference that I can believe? Do I start at the 3.3v pin on an Arduino and treat it as gospel? Or does a zener diode likely give me a better reference than a linear regulator? Are multimeters generally better at either measuring current or voltage, (internally of course they are the same but we hope they used low-tolerance circuitry), and is it generally better to try to measure near the middle of a range rather than at extremes? (Maybe volts rather than millivolts, or KV).
Are there any algorithms for "successive refinement" of calibration in the case that your resistors are at best 10% accurate, etc.
Thanks
Peter