Coax up to the sensor will add large offset. Use a 2wire/gnd mic cable for power and output freq with a cmos 555 timer at the end of your sensor. HCT, AC, HC invertors have increasing hysteresis respectively which is Vc and temp dependent (also, batch and manufacturer). 5% is probably the limit. Cmos 555 is fixed at 1/3Vc. Limit approaching .1% at low freq's and 15v supply. edit: ?? use two larger plates on the outside of the beaker for slightly higher C sensor; better S/N and linearity {strays}. I think you have just added eyelashes to the pig with lipstick... she's looking better 🤣
Well, when I mentioned coax cable I wasn't thinking of an RG58 with 100pF/m 😆 Anyway, placing the oscillator as close to your sensor as possible is indeed a good idea (though hard to implement with my breadboard setup 😅). I mentioned the use of an CMOS 555 and high impedance / low capacity analog comparators in the previous video. At some point I'll probably make some project (not tutorial) videos, that will cover all the nifty details of designing an actual capacitive liquid level sensor for a certain application.
You achieved good precision. I think using a coaxial cable can remove lot error ( Just guess😅). Sir, arduino serial port can delay many other instructions , maybe this is why frequency is not stable.
You are right, I definitely should use an coax / shielded cable. But I hope just for demonstrating the principles my hook-up wires will do 😅 And you're right about the Arduino serial port instructions too. It would have been better to insert a delay after them to make sure everything has been transmitted through the serial connection before making the next measurement.
Perfectr 👏👏👏
Thanks 🙂
Coax up to the sensor will add large offset. Use a 2wire/gnd mic cable for power and output freq with a cmos 555 timer at the end of your sensor. HCT, AC, HC invertors have increasing hysteresis respectively which is Vc and temp dependent (also, batch and manufacturer). 5% is probably the limit.
Cmos 555 is fixed at 1/3Vc. Limit approaching .1% at low freq's and 15v supply.
edit: ?? use two larger plates on the outside of the beaker for slightly higher C sensor; better S/N and linearity {strays}.
I think you have just added eyelashes to the pig with lipstick... she's looking better 🤣
Well, when I mentioned coax cable I wasn't thinking of an RG58 with 100pF/m 😆 Anyway, placing the oscillator as close to your sensor as possible is indeed a good idea (though hard to implement with my breadboard setup 😅). I mentioned the use of an CMOS 555 and high impedance / low capacity analog comparators in the previous video. At some point I'll probably make some project (not tutorial) videos, that will cover all the nifty details of designing an actual capacitive liquid level sensor for a certain application.
You achieved good precision. I think using a coaxial cable can remove lot error ( Just guess😅). Sir, arduino serial port can delay many other instructions , maybe this is why frequency is not stable.
You are right, I definitely should use an coax / shielded cable. But I hope just for demonstrating the principles my hook-up wires will do 😅 And you're right about the Arduino serial port instructions too. It would have been better to insert a delay after them to make sure everything has been transmitted through the serial connection before making the next measurement.