"This circuit was created in a local amplifier designing workshop done by Mr. Joshy Liadel."
Mr. Liadel has an audio sales and service business in Thrissur, Kerala,, did not check deeply.
Just see how different his circuit is from the regular circuit in the app note for the TIP41.
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwiHm7zL37D3AhUN8XMBHRgpC8UQtwJ6BAgMEAI&url=https://www.youtube.com/watch?v=MZNd5SKdmZI&usg=AOvVaw1bBgMv3Ss5OJOglgJDnC2N
It is the local language there, he is doing something on a whiteboard, I did not see the video, as that language is difficult for me.
But education is involved.
In Baroda also, the MBA courses have teachers on call who actually work in different organisations, and teach a particular course, they are paid per class taken, they are called contract teachers.
Mr. Liadel has an audio sales and service business in Thrissur, Kerala,, did not check deeply.
Just see how different his circuit is from the regular circuit in the app note for the TIP41.
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwiHm7zL37D3AhUN8XMBHRgpC8UQtwJ6BAgMEAI&url=https://www.youtube.com/watch?v=MZNd5SKdmZI&usg=AOvVaw1bBgMv3Ss5OJOglgJDnC2N
It is the local language there, he is doing something on a whiteboard, I did not see the video, as that language is difficult for me.
But education is involved.
In Baroda also, the MBA courses have teachers on call who actually work in different organisations, and teach a particular course, they are paid per class taken, they are called contract teachers.
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Question in my mind was the reason for designing the PCB.
Which is simple in software.
The tedious part is the actual pattern transfer, etching, drilling and testing.
Mr. Kannan admits that he can get that done almost overnight.
So why do the design work? And just that, not make the thing?
Answer is that it is an academic requirement....the student has to show his/her notes and work sheets to the examiner.
Which is simple in software.
The tedious part is the actual pattern transfer, etching, drilling and testing.
Mr. Kannan admits that he can get that done almost overnight.
So why do the design work? And just that, not make the thing?
Answer is that it is an academic requirement....the student has to show his/her notes and work sheets to the examiner.
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Thank you all for the suggestions. Here is a PCB layout made incorporating some of them. Please suggest corrections and improvements
board size is 4x3 inches
board size is 4x3 inches
Looks pretty good. Might need some small heatsinks on driver transistors. Mounting holes at front probably need more clearance to avoid spacer shorting trace to chassis. LTP transistors could be closer together so that they can be physically coupled better.
What happened with C11 and C12 (I think that's what they are, the latest circuit diagram is of a very low resolution, can't see anything...)
Apart from the layout discussion, I wonder if it is intentional or not that the output darlingtons in the 1st schematics are zero biased, which inevitably will produce tons of zero crossing distortions? The 2nd suggestions is much better with this respect, and with many others.
Best regards!
Best regards!
Hello @madhukannan Can you send (if possible) the PDF to print the circuit? I am interested in making an amplifier and your project is really interesting for me, I will make the circuit with the iron method.
Thank you very much
Thank you very much
True but that's a problem with plain diode biasing: it is not adjustable, you always go in "one diode" 0.65V steps.
"In theory" 4 diodes are needed because you have 4 BE junctions (2 Darlingtons) but in practice that's too much, power transistors get WAY over biased and thermally run out.
3 diodes as shown falls short but at least amp works and doesn't self destroy.
Solution is, of course, to use an "amplified diode ", a transistor with a bias trimmer so you can precisely adjust bias current to, say, 20mA or so.
But for a "school practice" design, it is acceptable.