you are truely amazing...and this circuit too! i loved it...and just tried it out..i was so impressed!! now gonna show this "magic" to my whole family !
That's great, but how about capacitive touch, thru insulation or paint? I'm trying to build such an circuit using painted frame in battery operated lift device as touch area to turn in led light.
Minimum potential required to forward bias the transistor is 1.4V then from where does the transistors are getting forward biased?? By that single wire??
a/q to me when he touches the wire the Electric Pulse generated by our get amplified by two cascaded amp which glows the led i am not very sure with my arg..
ok, I understood why its amplified and all that , but why is there even a minute amount of current in your body ? is it bcoz of nerve impulses ? that means this circuit won't work for other things ? :(
Blood contains ions thus making current be able to flow in your body. A human has also really low resistance due to the amount of water we have in our bodies. This circuit he has amplifies really small inputs, such as the flow of ions in blood.
Keilara Kappa It makes sense that current is able to flow inside our bodies as blood contains ions. But how does this current flow in our blood cause current flow on the outside of our skin, in this case the outside of his finger?
As I said, our bodies does have some kind of resistance, allowing us to act as a conductor. I believe that an average human has around 1k-100k ohm resistance depending if our skin is wet or dry.
Keilara Kappa Ok that makes sense, I understand that we are a conductor and we can act as a resistance. But we are not a generator or a voltage source! Imagine sticking a resistor of any value between 1k-100k (as you say human body can be, which I understand) in the schematic where the fingers currently go. How would that conductor/resistor actually inject current into the base of the BJT? The value of the skin resistance would definitely determine the amount of current for a given voltage source, but in this case there is no voltage source it seems!
Sir I'm having an issue with this circuit. I tried making this circuit on Proteus. But for the wire touching the hand I connected a touchpad there but when I run the simulation, the lead glows by itself even before we touch it with the hand. Pls help .
nerves works on ions differences (chemical interactions) inside nerve cell and outside , mainly from difference between K+ and Na+ (from -35 millivolt to 90 millivolt) for each cell.
nikhil muriki our hand works as a bery high resistance device. Here see his right hand is touching thebpositive side of battery. So he completes the circuit to the basebof Darlington base by a very high resistance. But aince Darlington has very high current gain the transistor gets to saturation and led lights up
Abhay Singh follow the specification chart of bc547 for ebc config and check led polarity put high resistance of 470 ohm with 9v for not let it burn and remove shoes and stand on ground while touching wire
you are truely amazing...and this circuit too! i loved it...and just tried it out..i was so impressed!! now gonna show this "magic" to my whole family !
7 years, and it's still as relevant as it could be
Thank you for explaining and experimentally demonstrating such a useful touch sensor
omg , you are the best dude , I'm learning so much from you
thank you , keep going bro
What about the power drain will it be always on
Touch sensor!!!!! .... Great explanation ... Bro..... 👌👌👌
You really used only a wire? This is amazing
very good Neso and What number of transistor did you use in this circuit?
you are great sir please make such more videos
That's great, but how about capacitive touch, thru insulation or paint?
I'm trying to build such an circuit using painted frame in battery operated lift device as touch area to turn in led light.
Minimum potential required to forward bias the transistor is 1.4V then from where does the transistors are getting forward biased?? By that single wire??
Nice demonstration👌👌👍
Nice video sir
ik deer
a/q to me when he touches the wire the Electric Pulse generated by our get amplified by two cascaded amp which glows the led
i am not very sure with my arg..
Using PNP transistor SK100 .
for same out put
Why your right hand is touching with battery ?
Sir you are touching other finger to battery positive side ,you should have to mention it without that it will not work
Great Video
sir I want to see your face
Did you forget to mention that your touching the other side of the battery using your body as resistor
Awesome... touch sensor 😊
I didn't understand. How can LED get forward biased by just touching the wire?? Somebody make me understand this.
ok, I understood why its amplified and all that , but why is there even a minute amount of current in your body ? is it bcoz of nerve impulses ? that means this circuit won't work for other things ? :(
If ie is the output ct. and in is the input ct. Is the transistor in cc configuration
liked it sir ... keep it up
okay deer
Why do your fingers touching the wire cause there to be current going into the base of the first NPN transistor?
i also have same question @neso guys
Blood contains ions thus making current be able to flow in your body. A human has also really low resistance due to the amount of water we have in our bodies. This circuit he has amplifies really small inputs, such as the flow of ions in blood.
Keilara Kappa It makes sense that current is able to flow inside our bodies as blood contains ions. But how does this current flow in our blood cause current flow on the outside of our skin, in this case the outside of his finger?
As I said, our bodies does have some kind of resistance, allowing us to act as a conductor. I believe that an average human has around 1k-100k ohm resistance depending if our skin is wet or dry.
Keilara Kappa Ok that makes sense, I understand that we are a conductor and we can act as a resistance. But we are not a generator or a voltage source! Imagine sticking a resistor of any value between 1k-100k (as you say human body can be, which I understand) in the schematic where the fingers currently go. How would that conductor/resistor actually inject current into the base of the BJT?
The value of the skin resistance would definitely determine the amount of current for a given voltage source, but in this case there is no voltage source it seems!
What is the use this combination ?
which npn transistor shall i use BC547 transistor
That will work
Sir I'm having an issue with this circuit.
I tried making this circuit on Proteus.
But for the wire touching the hand I connected a touchpad there but when I run the simulation, the lead glows by itself even before we touch it with the hand.
Pls help .
why the light do not glow when we do not touch the wire as the circuit is completed already ?
super sir
Just by touching the wire how a transistor can be forward biased??
Sir this is common emitter transistor so input is base and output is collector but we connected emitter of first transistor to second base why?
Do you make videos on analog communication?? Because I not finding it..
Sir one question,how the Darlington transistor do the amplification without biasing the transistor?
We are simply using it as an On-Off switch. Biasing is required when we need to amplify an ac signal for faithful amplification.
Here, Darligton transistor CE is biased by 9V battery and BE is biased by simply touching with our fingers
HELLO THERE . THERES A TIP142 NPN TRANSISTOR IM TRYING TO USE IN MY ONE TRANSISTOR SOUND AMP . SO TELL ME HOW THE CIRCUIT WILL LOOK LIKE ??? THANK YOU
Tip142 is a Darlington transistor with high gain, not really suited fur an amp
Sir, how can transistor is active? I mean, the vbe of 1st transistor is too low (less than 0.7)
Please help me with this.
You pickup enough voltage on your body to forward bias the 1st transistor slightly, which then forward biases the 2nd transistor even more
the voltage input is between the base and collector the terminals.
so where does the input voltage come from ?
nerves works on ions differences (chemical interactions) inside nerve
cell and outside , mainly from difference between K+ and Na+ (from -35
millivolt to 90 millivolt) for each cell.
Your body acts as an antenna and picks up very small voltage mostly from your household AC wiring
@@hartyguyton3800 So the input voltage from body just mV can be amplified to drive the transistor to work. Am I understand correct?
Correct! Actually mv inside the body but what drives this transistor is microvolts that's why darlington is needed.
How touching effected to current flow
Can you explain me how the hand is working as source in this experiement
nikhil muriki our hand works as a bery high resistance device. Here see his right hand is touching thebpositive side of battery. So he completes the circuit to the basebof Darlington base by a very high resistance. But aince Darlington has very high current gain the transistor gets to saturation and led lights up
Super
Sir in this model we use which type of npn transistor
Just the 'regular' bipolar transistor such as an 2N2222, which is a very common and cheap NPN transistor
Not working with two npn transistor.
we need to touch the wire and resistor
Neso Academy mine is not working i used bc547 transistor
No, its working only if we touch the wire and the resistor!!
Vrahul Veeravelli remove your shoes and stand on the floor
Abhay Singh follow the specification chart of bc547 for ebc config and check led polarity put high resistance of 470 ohm with 9v for not let it burn and remove shoes and stand on ground while touching wire
Darlington pair 🤭✨
This is also working without sensor wire🙄