THE FIELD NOTES
Our methods
See where a claim comes from, and where it stops.
A claim should carry enough context to check it. We distinguish what a document says, what a calculation assumes and what an experiment actually measured.
Four kinds of evidence
| Label | Meaning |
|---|---|
| Source-based guide | Our explanation of identified publications and their limits |
| Calculated example | Arithmetic with stated assumptions; no experiment implied |
| External measurement | A result attributed to its original author, sample and conditions |
| Original measurement | Our own documented experiment; none is included on these pages |
What an original instrument test must include
Calling a result an original measurement requires sample provenance, model and revision, relevant firmware, original photographs, function and range, reference instruments and calibration status, environment, connection method, settling time, repeated readings and raw data. The result has to state its limits and keep as-received performance separate from adjusted performance.
Long-term results require dated comparable observations. Owning a sample for several years alone is not a reliability study. A calibration comparison is not a safety certification.
Keep a record
The download contains column headings and one empty row, without fabricated sample readings. It is a documentation aid, not a test procedure.
Download blank measurement record ↓How we select and cite sources
We prioritise identifiable original work and documented methods. Independent author sites, manufacturer publications, regulator guidance, standards information and community questions serve different purposes. A forum question can reveal a problem but does not establish a correct answer.
The measurement notes cited here include HKJ for structured measurement methods, Gough’s Tech Zone for setup limitations, and Mark Hennessy for detailed instrument observations. We attribute their work rather than re-publishing their photographs or presenting their results as ours.
Review, revisions and corrections
These guides carry the Meter & Probe byline. That byline is not a review by a named electrician, metrologist or certification laboratory. This site does not publish UK installation procedures. A named reviewer is credited only for work they actually reviewed, and no such credit appears on these pages.
The date on a page marks a substantive review of the text or sources. It does not mean an instrument was tested that day. Corrections identify the changed claim and its basis. Corrections with the page, passage and supporting source.
Commercial relationships
The operator also owns instrument retail sites. A related retail link is commercial context, not independent evidence. Such links will be disclosed beside the link; ownership never substitutes for testing. See our commercial disclosure.
Policy text reviewed 22 September 2026.