Calibration

The measurement accuracy of the product will change over time due to aging of the parts and different environmental conditions. This mainly affects offset and amplitude of the analog stage as well as the internal clock reference. To kepp this changes as small as possibel, all Spectrum products are equipped with high accuracy voltage calibration spource and high-accuracy clock sources. The calibration source is used for an internal software calibration..

Calibration Cycle

In general, the decision on calibration will depend on the application and requirements of the customer. We recommend running a software calibration after warm up and if there is any significant operational temperature changes. If the customer requires calibration against known standards then it is necessary to perform a factory calibration. If this is needed we would typically do it once per year. A factory calibration requires the units to be returned to Spectrum so that we can retest all of the specifications (including the accuracy figures as shown in the attached data sheet) against calibrated and traceable instruments and issue a full calibration report.

Internal calibration

All Spectrum Digitizer products contain an internal high accuracy calibration source. This one is used to cover accuracy changes due to temperature and environmental changes. Environmental changes also include changes on the host system where the card is mounted. Running an internal auto calibration needs to be run after complete warming up of the system an the card. Please note that the accuracy specification of the data sheet is valid after warm-up and after internal calibration.

Local calibration verification

An alternative to the factory calibration at Spectrum would be a calibration check at a national calibration lab that you select locally. This one can check the accuracy after internal calibration of the card against external traceable standards and document the product being inside a desired specification.

As an external lab can't access settings of the internal calibration source there might be an issue if the calibration check fails and the card has to be sent back to Spectrum for factory calibration.

Factory calibration

In factory calibration the internal calibration source and any adjustment settings are calibrated against an external traceable calibration source. The factory calibration covers any aging and temperature changes of the calibration source and all calibration related parts of the hardware. Please note that even directly after factory calibration an internal calibration at your location may be necessary as the factory calibration system and factory calibration environment differs from your system and environment.

ISO17025 Certificate

Since 2026, Spectrum is offering an additonal formal calibration certificate following the ISO17025 standard. This certificate can be ordered together with a factory calibration or upon purchase of the card.

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