[time-nuts] Input filter for data logger
holrum at hotmail.com
Sun Nov 19 20:20:45 EST 2017
Here are Wenzel's input circuits:
The TAPR TICC uses a slightly modified version of the two transistor circuit.
Also check out the LPRO-101 manual for their versions of the single CMOS gate squarer. One thing they do is add an RC filter to the CMOS gate power supply.
I use this version (with a 74HC86 as the input gate) on my HP-531xx time interval calibrator circuit. Wenzel says an HC gate works better than AC logic if you don't need to handle higher freqs. It provides surprisingly good performance for such a simple circuit.
More information about the time-nuts