Signal generation and measurement EN_CLOCK_GEN This module is based on the 3 channels version of the Si5351 clock generator chip. The compact board integrates an SI5351 clock generator, a micro controller...
Today I came across some very interesting videos about professional frequency measurement error ( Agilent 53131A Frequency Counter Oven Upgrade) and it gave me the idea to better the precision of the frequency counter I am working on.
I was quite happy until now with the accuracy of about 100 ppm measured on the Arduino compatible frequency counter, but I realize that it is probable that we can get 1 order of precision better just (with a redesign…) by using a much better crystal oscillator. Until now I opted for a regular 16 Mhz crystal and if one considers what is reported on this discussion about the Arduino clock frequency accuracy it appears that the 100 ppm error that I measured is very coherent with the error due to the clock. So probably we could get down to 10 ppm or less using a more accurate clock.
Then I found that this Abracon LLC ASVTX-09-16.000MHZ-T TCXO might be a not too expensive solution. It has a frequency accuracy of +/- 2.5 ppm.
But I need some more information on using this TCXO instead of a standard parallel crystal.
What is your opinion about this? Do you know about a successful clocking of the Atmega328p using a 16 Mhz oscillator with an error under 10 ppm ?