Advanced Qualification · A-003 Measurements · A-003-004-005
If a frequency counter, with a time base accuracy of 10 PPM (parts per million) reads 146 520 000 Hz, what is the most the actual frequency being measured could differ from that reading?
- A 1465.2 kHz
- B 1465.2 Hz
- C 146.52 Hz
- D 146.52 kHz
Correct answer: B — 1465.2 Hz. From the official ISED question bank, verified word for word.
Why
A time base accuracy of 10 parts per million means the reading can be off by 10 Hz for every million Hz measured. The full explanation — and one for every question — is in Pro.
Practise this section
Measurements: meters, oscilloscopes, counters, signal generators, and what a reading actually tells you.