How Can I design a OCL AMP?

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Help Me With My OCL AMP Design, Thanks

How Can I design a OCL AMP?

Is it possible to put mutiple transitors together in diffrent configurations and then it will work?

using common emiter set up then a common collecter set up
I had shorted the output of pnp and npn trasntiors, it works fine and has the correct idle current which I wanted it to be, 20MA.

Plorbem is that I am getting no sound. I have excatly 0 volts in the speaker
but it is not amplifiing any sound

TransistorAmp circuit design software for bipolar transistor amplifiers
I used trasntior amp for design but I haven't used any load resitors.
I am guessing even if I had used load resitors it wouldn't work

Load resitors i am reffering to for common emiter is r3
Howto design a transistor amp in common-emitter configuration with TransistorAmp 1.1 software

and also r3 for common collector
Howto design a transistor amp in common-collector configuration with TransistorAmp 1.1 software
 
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rayma

Member
2011-04-29 8:37 pm
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natad123

Member
2015-10-02 7:12 am

MR Overclock

Banned
2016-06-12 11:17 pm
Whats happening here is that I am having no sound at all.
I don't have a feed back loop either, just trying to get some sound comming out of the speaker.

I'm tyring to use a common emiter setup to gain some voltage then feed that into a common collecter set up. then use npn and a pnp to make it ocl.

I have the out puts of the emiter and collector set up shorted, so the dc voltage is zero since the trasntiors will give out the dc voltage at the out put due to the dc voltaged usied to bias it, thefore it needs a capacitor at the out put to block the dc voltage.
 

MR Overclock

Banned
2016-06-12 11:17 pm
Thanks for the help guys, heres what I had built.
I had also tried chaging to a common base instead of emiter for the voltage gain stage.
Since I thought 50k input inpediance could be too high so i am getting no sound.

The common base had 1.3ohms input inpediance but no sound either
same idle current, both sides postive and negative side idle current is at 20ma, seems a bit odd though
should I be getting 40ma both sides instead of 20?

Also if I tap the speaker, it seems to be stuck in the middle,
and it i push the speaker in and out enough the back voltage caused by the inducatance of the speaker will blow my tip41c

refer to the circuit with just the circuit diagram,
 

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MR Overclock

Banned
2016-06-12 11:17 pm
Sorry for the doubble post, but it dosen't seem like I can edit my old post any more

Heres the two solutions I had come up with, which could solve the plorbems but I have not tried them yet.

What I would do is remove the shorted together outputs of the common emiter stage, then add a load resitor, input to next stage, but then next stage dosen't have any biasing resitors then connect to speakrers.

The other solution is doing the same thing as above but not having a load resitor
 
So I currently have the drivers connected in common base operation
removed the shorted out puts of the and shorted inputs of the common base configuration.

I then feed the output of common base into the common collector without any biasing transitors, inserted a 33 ohm reistor load and powerd up. Zero idle current flowing

Seems like the plorbem here is the common base or common emitter configuration biasing is not working porperly? I have connected every thing up using the diagram I got from transitor amp, but have not connected a load resitor.

So it seems like currently, the side on the right is working fine, common collecter set up. but the stuff on the left is not ok.

Added the load resitor, and it seems to be biasing the common collecter transitors with too much voltage
(instead of working as a load resitor it became the biasing resitor instead),
I am getting 0.5Amps and 0.7Amps on postibe and negative supply. Used a 1K for load resitor and transitor amp says the value should be 1.3K

I know common collector setup has no voltage gain, does it have enough gain to put out some sound?
Would it have enough gain if I use a few stages of common collector setup folowed by common collector set up
 
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