Which thermal camera features change what you can actually see
Native detector pixels, thermal sensitivity and emissivity control change results. Upscaled resolution, palettes and storage capacity do not.
Read Article→Learning Center
Plain-language explanations of the measurements, sensors and numbers behind environmental monitoring.
What makes a CO2 monitor reliable, and why that is not the same as accurate
Accuracy is where a monitor sits today. Reliability is whether it stays there once the lamp ages, the optics gather dust and the room stops emptying at night.
Read Article→Using an inspection camera in a drain, and where a borescope stops
A handheld borescope inspects traps and short branch pipes, while anything beyond the first few metres of a lateral needs a push rod reel, and the limit is set by focal range as much as by cable length.
Read Article→How to read an air quality monitor without over-reacting to it
Which values on the screen deserve a response, which units they are in, and why the colour band is a manufacturer decision rather than a reading.
Read Article→How an air quality monitor works, sensor by sensor
Each channel on an air quality monitor is a different physical sensor with a different operating principle, and one of the numbers on the screen has no sensor behind it at all.
Read Article→How to make a hygrometer, and which homemade version really measures
Of the four things people build when they set out to make a hygrometer, only the wet and dry bulb psychrometer produces a number you can defend, and the arithmetic behind it is short.
Read Article→How to test a hygrometer, and what a passing result actually proves
A saturated salt reference gives one known humidity point at one temperature, which is enough to catch a broken hygrometer and not enough to call one accurate.
Read Article→Wiring a thermocouple to watch a wood stove catalytic combustor
How a thermocouple probe, matching extension wire and a cold junction compensated readout fit together on a catalytic stove, and which room instruments answer a different question.
Read Article→What makes a digital multimeter accurate, and how to read the number
Multimeter accuracy is a percentage of the reading plus a fixed number of counts, and the biggest errors on a real measurement usually sit outside that specification.
Read Article→Replacing bearings on a multimeter knob: what is really in there
A multimeter rotary switch has no bearings, and the three faults people blame on them are a detent spring, a contact surface and a cracked rotor.
Read Article→How to check earthing with a handheld digital multimeter, and what it cannot measure
A multimeter can confirm that an earth is present, connected and at roughly the right potential, but it cannot measure electrode resistance or earth fault loop impedance.
Read Article→Can a hygrometer be calibrated, or only checked and corrected?
Most consumer hygrometers cannot be adjusted at all, but any of them can be verified against a saturated salt reference and carried with a written correction.
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