A NEW WEEK, A NEW QUESTION.
My question is based on the circuit in this toppic so I am not starting a new one.
I have built a couple of pulse delay modules with the CD4093 (NAND Schmitt Trigger). In my stock of IC's I have several CD4093 but with different batch numbers ( I think these are batchnumbers). For instance the 19AA3F 8E4 and the 21AA3F 8E4. The numbers are printed above the printed CD4093 marking . These IC's are not functioning in the pulse delay module where others with other batchnumbers are functioning perfectly..
What is not functioning:
The delay time and pulse width can not be adjusted with these specific IC batchnumbers. The IC doesnot trigger the output when it receives an input signal.

Questions?
1. What is the reason that these specific IC's are not functioning in this circuit whereas in other circuits (which I have built) these operate flawless?
2. What do you need to get the correct answer to this question?
3. Can I use a CD4011 (NAND) in the pulse delay module without problems ?
(I have tested the CD4011 in the pulse delay and it does function!!)
4. What is the Schmitt Trigger doing in the original circuit publication?(see #45)
My circuit is based on RISING and FALLING edge detection (see below)

What is Schmitt Trigger: (source:https://howtomechatronics.com/how-it-works/electrical-engineering/schmitt-trigger/)
" The Schmitt Trigger is a logic input type that provides hysteresis or two different threshold voltage levels for rising and falling edge. This is useful because it can avoid the errors when we have noisy input signals from which we want to get square wave signals. So for example, if we have a noisy input signal like this, that is meant to have 2 pulses, a device that has only one set point, or threshold, could get incorrect input and it could register more than two pulses. If we use the Schmitt Trigger for the same input signal we will get a correct input of two pulses because of the two different thresholds. So that’s the primal function of the Schmitt Trigger, to convert noisy square waves, sine waves or slow edges inputs into clean square waves. "

Your answers will be appreciatedas always!
Thanks
Henry

 

Consider that on the full device specifications sheets there are ranges given for many of the specifications, not a single number.
What those numbers mean is that MOSTof the devices variables will fall within that range, but no promise of that except for the expensive HI-REL devices that are all tested individually. So widely different threshold values will often affect performance in some circuits. That is why we are given the data sheets, so that we can design around the variability.
And that code that was given shows both production run and probably assembly line codes. So probably both devices are the same manufacturer and line, but very different dates.