NPL's timing and quantum laboratories support characterisation of clocks, magnetometers and the occasional hopeful datasheet.
Campaigns are scoped as work packages: what is measured, against what, and what the report will be allowed to say.
That last clause is the one companies find surprising. A traceable measurement is a statement about a specific device, under specific conditions, with a stated uncertainty. It is not a general endorsement, and NPL will be scrupulous about the difference. Firms who understand this get an extremely powerful document; firms who wanted a marketing quotation get a courteous disappointment.
The campaigns are most valuable before a claim is published. Establishing what your device actually does, against a primary reference, is considerably cheaper than defending a datasheet figure to a customer who has commissioned their own measurement.
Specification
- Primary frequency references
- Quantum sensor characterisation
- Traceable reporting
- Magnetically shielded measurement environments
- Long-baseline frequency comparison capability
- Documented uncertainty budgets for all reported quantities
What it is the right answer to
Jobs this facility genuinely suits.
- Independent verification of a clock or oscillator stability claim
- Characterisation of magnetometer sensitivity, noise floor and drift
- Calibration of a reference instrument that will underpin your own measurements
- Establishing a traceability chain ahead of regulatory or customer scrutiny
- Resolving a disagreement between two parties' measurements of the same quantity
What to bring
Turning up without these costs facility hours rather than bench hours.
- The device, with its intended operating conditions clearly specified
- The exact claim you wish to test, expressed as a quantity with a range
- Any prior measurement data, including results you found puzzling
- A decision on who may see the report and what it will be used for
What you leave with
- A traceable measurement report with a full uncertainty budget
- Raw comparison data against the reference used
- A clear statement of the conditions under which the result holds
- Where relevant, an opinion on whether your claim is supported
Limitations
Worth knowing before you write the proposal.
- Results apply to the device measured, not to a product line
- Devices that are not yet stable enough to characterise will be identified as such, which is useful and unwelcome
- The laboratory environment is quiet; your operating environment will not be