QUESTION:
I had tested 2 different output (2MB & 2KHz) with a frequency counter. The result shown for o/p 2MB is stable and but for 2KHz the value is 2048001/2/3. Is this normal?
ANSWER:
The phenomenon you are observing is not uncommon. If you observe the waveform of the 2 Mb signal you will see very sharp edges and the counter is able to discern very accurately and precisely the position of the zero crossings. A 2 MHz is an analog waveform and if the slicing threshold of the counter is not set accurately then the counter could have some uncertainity as to the precise position of the zero crossing. Also, if the signal level is too low, or the signal is not properly terminated, noise and/or reflections may cause the counter to make false detection of zero crossings, causing the 2048001/2/3 effect.
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