I don't know why my BJT circuit is not working
Hello.. I want to ask a question!..
I am learning about bjt.. so while practicing it circuit on breadboard i thought to increase the audio coming from my earphone..
So it cut the earphone wire and put it left and right audio wire to base and ground wire to battery ground, and I connect speaker to collector in series and emitter to ground but no audio is coming from speaker.
16 Replies
@Joseph Ogbonna
Can you give a circuit diagram of what you did. Your connection
Like this
You will need to provide the type of transistor being used also l. I will try to run a simulation on this. The speaker type also needs to be considered.
2222N
And for the speaker I took it out from the old nokia phone
Idk.. why it is not working
From what I have learned base is act as switch. So when the sound come from the wire of cable it should turn on the bjt and complete the connection and speaker produce sound.
So basically it converts small sound from the earphone cable to 5v
But nothing is happening
🥲this is the first circuit which I made with the help of my mind
Without looking from anywhere
That's a good start
I will send you a basic circuit you will try also
It will work
Thankyou so much
But I also want to know the reason why it is not working
Base current is less than the collector current
Still it is not working
Solution
There is no resistor configuration in your circuit
I have tried it by putting resistance
150ohm
It doesn't work
Then I tried
220ohm
Still don't work
Use the instructions here to create your new design
https://www.instructables.com/2222A-Transistor-Amplifier/
Instructables
2222A Transistor Amplifier
2222A Transistor Amplifier: Hii friend,
Today I am going to make a transistor amplifier.2222A Transistor we will use to make amplifier.This amplifier is really working.This amplifier can use to make a mini amplifier.
Let's get started,
What is the need of capacitor there?
More over why the collector is in reverse bias?
It shouldn't be in forward bias
It's a 2222A transistor so check the datasheet to confirm
Can you explain this too?
@SageBoy It is a coupling capacitor to "filter" DC current. Use the Internet seach engine and look for how amplifiers work.
Frankly, I would not start with amplifiers. I would start with low-frequency oscillators, switches, flip-flops... Something you can visually control without expensive equipment.
Yeah!.. I got it about now, it use to filter signal, it block DC signal and allow ac signal to pss through it
Oh!..ok sir, i have not started with amplifier , it is just like that the lecture was about bjt in course and after learning about it, i was thinking what I can do with a bht which is like a electric switch and this came into my mind. I thought that if I give my phone audio signal in base to turn on and off bjt and allow my 5v current to flow from it to emitter that I can produce large sound.. but now I find that things don't work like this