I have been watching videos about biasing simple bjt transistors and choosing the values of the components around them for several years, and never really understanding what I was doing. After watching these three videos, and wondering if he really was going to say everything 47 times, I realize I am much closer to really getting this. Not just being able to do it, but getting it. I figure another 3-4 watches (3+4/2=3.5x47=164.5 times) and I will have it. Thank You! Looking forward to what else you might get through my thick skull.
At long last someone bothered to explain the load resistor and that makes the rest of the design crystal clear. I literally want to shake your hand right now, but please take a heart felt thank you from me for such a brilliant tutorial. I’m off to burn out some 2N2222s tomorrow just to proveI now understand where the various voltages and currents come from! You feel free to have a virtual beer from me! Now I shall hit the subscribe button and the thumbs up. Can’t wait to work through your other tutorials, you teach so practically.
I have seen many videos and I have tried to do the same things, but without results. until I've studied the three videos on common emitter amplifier. It has become clear to me the reason and the reason for the different components in this type of circuits. Many thanks.
What an educational achievement! I have never learned so much in such a short time. And I have a brain that is not really wired for this type of knowledge
10µF indeed provides a better sound with less distortion, I've tried the same circuit (except for the transistor which is a BC547) and it works quite well actually ! Thanks man ! I wish there was much more on this, to make a real amp, but hey, that's cool man !
An awesome video. Really enjoyed it. My understanding is that the VCE voltage is about 0.3 V and even much higher for power transistors. Why don't you consider this voltage? It's somewhat significant, and is certainly not zero. It should not be forgotten or left out. I would appreciate a response to clarify this for me. Thank you for all your efforts. Love your stuff.
Well done! It's very clear. Your Volume Control seems a little strange as most folk would ground one end of the Potentiometer Track so that it can be turned all the way down. Also an Eight Ohm Loudspeaker seems rather too heavy a load for this circuit although it would probably work to some degree.
But what about input impedances? Is it Line level? It does seem like a line level. Either you are pretty lucky to choose this load or you just tested a lot.
I don't understand why you say that the speaker uses 0.25 watt (or close to that) with your 470 ohm resistor. Because, when I use a simple voltage divider formula then I come to a total of only 0.0028 watt for the speaker. I did this: Voltage supplied to speaker = (8/478)*9v = 0.15v Total current draw = 9v/478 = 0.0188 Ampere Power used by speaker = 0.15*0.0188 = 0.0028 Watt What am i doing wrong in this calculation?
At that point in the video, I'm talking about the total power going through both the load path and the transistor path, not just the load. I was talking about how I wanted to be careful because I was designing a power-hungry amplifier with weak and cheap parts, and if I were doing it "for real", I'd use actual power resistors and transistors that could handle the load the speaker actually wants.
85 microamps was rounded a little for clarity. The actual exact resistance was 1997 ohms. The reason I used 1800 ohms for the actual resistor was that I wasn't using a trimpot to get an exact resistance: I was using just a standard box of resistors, and 1800 was the closest one that was no higher. The resistors R1 and R2 form the bias part of the amplifier, and they have to supply a minimum amount of current to the transistor's base, which means it is perfectly fine for them to be lower than needed (excess current), but it is not fine for them to be higher than needed (not enough current available), so I went down to the closest available discrete resistor value available to me.
@@simplyput2796 Thanks for answering me. I'm doing and studying the same circuit and learning a lot. Thank you. By the way ... could you explain how to do an amplification but with an operational amplifier. I understand that it's simpler, but I like the way you explain every detail. As always many Thanks.
I have been watching videos about biasing simple bjt transistors and choosing the values of the components around them for several years, and never really understanding what I was doing. After watching these three videos, and wondering if he really was going to say everything 47 times, I realize I am much closer to really getting this. Not just being able to do it, but getting it. I figure another 3-4 watches (3+4/2=3.5x47=164.5 times) and I will have it. Thank You! Looking forward to what else you might get through my thick skull.
At long last someone bothered to explain the load resistor and that makes the rest of the design crystal clear. I literally want to shake your hand right now, but please take a heart felt thank you from me for such a brilliant tutorial. I’m off to burn out some 2N2222s tomorrow just to proveI now understand where the various voltages and currents come from! You feel free to have a virtual beer from me! Now I shall hit the subscribe button and the thumbs up. Can’t wait to work through your other tutorials, you teach so practically.
I have seen many videos and I have tried to do the same things, but without results. until I've studied the three videos on common emitter amplifier. It has become clear to me the reason and the reason for the different components in this type of circuits. Many thanks.
What an educational achievement! I have never learned so much in such a short time. And I have a brain that is not really wired for this type of knowledge
I appreciate your humor, thank you so much for taking the time through this. The comments show that this video is a bit an oasis, thanks!
Finally something what works for me. Thanks!
Was hanging on by my fingernails (but hanging on) and then came your blessed summary!
Yowzah!
A keeper! You are terrific!
this guy is like a professor great stuff
10µF indeed provides a better sound with less distortion, I've tried the same circuit (except for the transistor which is a BC547) and it works quite well actually ! Thanks man !
I wish there was much more on this, to make a real amp, but hey, that's cool man !
I feel blessed to find your channel!
Better late than never.
Thank You
An awesome video. Really enjoyed it. My understanding is that the VCE voltage is about 0.3 V and even much higher for power transistors. Why don't you consider this voltage? It's somewhat significant, and is certainly not zero. It should not be forgotten or left out. I would appreciate a response to clarify this for me. Thank you for all your efforts. Love your stuff.
Consider the venerable 2N2222A Small−Signal Current Gain
(IC = 1.0 mAdc, VCE = 10 Vdc, f = 1.0 kHz) (IC = 10 mAdc, VCE = 10 Vdc, f = 1.0 kHz)
hfe
50-75 (Min)
300-375
(Max)
Love your explanations man great job.super awesome
Good course! How we do calculate on + and - power supply?
Well done!
It's very clear.
Your Volume Control seems a little strange as most folk would ground one end of the Potentiometer Track so that it can be turned all the way down.
Also an Eight Ohm Loudspeaker seems rather too heavy a load for this circuit although it would probably work to some degree.
wow. you're so good at this. can it even get any better..?
Hi it has been two years sir. No new uploads?
But what about input impedances? Is it Line level? It does seem like a line level. Either you are pretty lucky to choose this load or you just tested a lot.
I don't understand why you say that the speaker uses 0.25 watt (or close to that) with your 470 ohm resistor. Because, when I use a simple voltage divider formula then I come to a total of only 0.0028 watt for the speaker.
I did this:
Voltage supplied to speaker = (8/478)*9v = 0.15v
Total current draw = 9v/478 = 0.0188 Ampere
Power used by speaker = 0.15*0.0188 = 0.0028 Watt
What am i doing wrong in this calculation?
At that point in the video, I'm talking about the total power going through both the load path and the transistor path, not just the load. I was talking about how I wanted to be careful because I was designing a power-hungry amplifier with weak and cheap parts, and if I were doing it "for real", I'd use actual power resistors and transistors that could handle the load the speaker actually wants.
@@simplyput2796Ow okay, then I missed that detail. Thanks for your answer
Hi, I get loss in the 17:54 minute,
did you say that 1.7v divided by (10 times 85u Ibq) is equal to 1990Ohms..?
85 microamps was rounded a little for clarity. The actual exact resistance was 1997 ohms. The reason I used 1800 ohms for the actual resistor was that I wasn't using a trimpot to get an exact resistance: I was using just a standard box of resistors, and 1800 was the closest one that was no higher. The resistors R1 and R2 form the bias part of the amplifier, and they have to supply a minimum amount of current to the transistor's base, which means it is perfectly fine for them to be lower than needed (excess current), but it is not fine for them to be higher than needed (not enough current available), so I went down to the closest available discrete resistor value available to me.
@@simplyput2796
Thanks for answering me.
I'm doing and studying the same circuit and learning a lot.
Thank you. By the way ... could you explain how to do an amplification but with
an operational amplifier. I understand that it's simpler, but I like the way you explain every detail.
As always many Thanks.
Yep, op-amps are coming! I have several other types of amplifiers to work my way through first, but they're in the pipeline.
@@simplyput2796 Goooood