Audio Amplifier on Transistors: Stereo Conversion, 2x17V Toroid Transformer & 2M Capacitor Marking

Hello, I found a schematic of a mono amplifier on the internet and converted it to stereo. Is everything ok after my connection? Of course, I will make a symmetrical power supply and the transformer I will use is a 2x17v toroid. And what is the marking of the 2M capacitor?

And what was that amplifier and in what class did it work? Seems like the correct diagram. However, I recommend modifying the schematic to that of the proven, good "Eltron 100" on slightly more modern transistors and you will have no problems and a pretty decent amplifier.

This amplifier, what I found, I only know about it that it is 30w, but I do not know the class or other specifications. Generally, I do not need an outstanding amplifier, but I need it for school as an analog circuit work.

This may be enough, but you should consider how the stabilization of the quiescent current is carried out (the teacher may ask ).
The most simple construction can be obtained on the old TIP142 / TIP147, BDX53 / BDX54, BDW83 / BDW84.

Link

The teacher is emm lazy to say. It does nothing in the lesson but requires. As for the projects, we already had one, and he only checked the board performance and operation, so I doubt he will ask for anything. So this scheme can be like this?

Now I'm a little confused. So I can use this schamt to build an amplifier or not.

I read what you wrote. But now my question. What amplifier should I make. I do not want it to be expensive to make because I will not use it on a daily basis, I will probably run it once in a while. It doesn't have to be very powerful either. But it must be on discrete elements

Added after 1 [hours] 54 [minutes]:

Ok, I found it already, whether it's good or bad, I hope that it will work and writes that Q3 and Q4 and IC are common for both channels and on the schamacie only the left channel is presented so I have to do literally the same as above to put these scams next to each other left signal to one right to the other or some other way to connect it. I would ask for a quick reply

You had said:
- follow the "Eltron 100" diagram, and use, for example, newer transistors such as 2SC5200 / 2SA1943, or 2SC3858 / 2SA1494 in the complete power stage, or only two 2SC5200 or two 2SC 3858 in a pseudo-circuit [/url] complete, in the control stage 2SC4793-2SA1837,




OR
- in the cheapest version, use Darlington transistors like the cheap BDX53 / 54, which will simplify the design to a minimum. Another example diagram:



( of course you can use a lower supply voltage and BDX 53/54 - similar to one of the versions of the amplifier in Zodiac - generally Unitra used one, practically more or less developed scheme ).

The diagram you provided is a Sinclair 30 study from 1969 . And here's a little more about its design. and on ours forum .

But above I wrote that I want something simple because it only gives back and get a grade .. I don't need 100w until. And would what I gave now be ok?

I can see that my friend has a vague idea of what he wants to do. It is enough to use a slightly lower power supply and with lower efficiency, possibly correct the gain and have a colleague amplifier 10-20-30W. It is enough to look at Unitra's constructions, such as the amplifier in the mentioned Zodiac, later Tosca, or the Dior WS422 set amplifier.
The amplifier from the BDX53 / 54 would probably have 20W / 8?. Also my friend does not like its simplicity?

The main point is that I have a vague idea of what I want to do because the teacher himself does not teach us much. He will come to say what to say and his work is over. He said make an amplifier on discrete elements so much information about it. I found something else 10w amplifier that I posted above and is it ok good and whether in stereo it looks the same as the first one

Opinions have already been written about the project you have chosen, and here, as well as in the materials that were recommended. If you want to make a stereo amplifier, you must necessarily duplicate the entire amplifier path for both channels, i.e. the voltage and current stage of the power amplifiers are performed twice. At most, the power supply is common, i.e. the bridge transformer and filter capacitors. You had it clearly explained.
I don't know why you choose strange constructions with such parameters, but also that can cause trouble.

Make a copy of any of the "Unitra" type amplifiers. Unless you also like a simple 3-5W amplifier, the design of which is simple and cheap (you can even use battery power, i.e. make something like a popular portable speaker).

Hello

I will propose such a solution:


1.It works for sure, and it's pretty good. Anyway, for some year it has been using a 4? loudspeaker

2. I can describe the diagram. It comes from the "Elektor" magazine so there are no problems with the quality of the solution. Very stable. In total, the commissioning consists in checking the voltage on the emitters of the BD679 / 680 transistors

3. Not many components, not bad parameters, for 80% I have a PCB design for it.

4. I have made a simulation of the system, if it was needed or for reference.

5. I recommend a solution
6. If this arrangement will not fit, I suggest also one Link I also put it together and it sounded pretty good, I only changed the diodes from stabilization to transistor ;)

Ps. I will not show a better diagram of the studio audio amplifier that we "tested" as a group in the studio because it is going to break down ...
greetings
EDIT:
In the circuit from "Elektor" emitter resistors should be added (I added 1?

[/url] The previous version of the amplifier from Elektor - even more simplified :



- only four transistors in total.

aaanteka wrote:

follow the diagram "Eltron 100",

Exactly; the same series also featured the Eltron 30 - the scheme is practically the same, the difference is two, not four, power transistors and a smaller power supply. At the same time, the amplifier is "idiot-proof" thanks to the use of a circuit that prevents excessive current flowing through the power transistors (eg in the event of an output short-circuit).
https://obrazki.elektroda.pl/44_1209907625_thumb.jpg