CISPR 32 Annex C section C.2.2.1 contains a requirement to identify emissions that are intermittent in nature and apply timing criteria to determine if the emission complies with the standard, irrespective of level.
This is a difficult measurement to make and requires the EMC engineer to firstly identify the emission and then to take a series of timing measurements in zero span mode to determine compliance.
To help EMC engineers with this requirement, we have designed a training aid that produces a radiated signal in excess of the limit and operates with three pre-determined "pass" timing sequences and three pre-determined "fail" timing sequences along with a random "pass" and random "fail" mode too.