I am building a digital voltmeter at school and my design so far relies on 2 clocks at about 10kHz and 19kHz. It seems as if it would be hard to achieve these exact frequencies with a simple 555 timer because of the tolerances of resistors and capacitors. We have a device which measures capacitance very accurately in the lab. I was thinking I could get pretty close to the desired frequencies with a couple of pot resistors that can be manually tweaked until you get the desired frequency on the oscilloscope.
I have read that crystal oscillators have exact frequencies and are used in many clocks and microcontrollers, but I am not sure how (if at all possible) one could adjust its frequency since they are all in the MHz range. I am open to any suggestions on how to get an accurate clock for the 2 counters I am using in a digital voltmeter.
I have read that crystal oscillators have exact frequencies and are used in many clocks and microcontrollers, but I am not sure how (if at all possible) one could adjust its frequency since they are all in the MHz range. I am open to any suggestions on how to get an accurate clock for the 2 counters I am using in a digital voltmeter.