Another science 🧪 project

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I know I really need an amp in need of repair.  Trust me ive been looking.

Anyhow I was flipping through a book looking for something cool and there is an experiment for creating and then abating crossover distortion.

Here is the plagiarised schematic

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Ensuing rats 🐀🐁 nest

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I managed to throw this together pretty quickly and to my astonishment it worked.  They called for 2.2 uf electrolytics the closest I had was 3.3 uf

I didn't even measure the input I just increased it from zero and BAM there it was on the output

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My instructions are to learn about the existing phenomena then take steps to cleanup the output by
-replacing one of the 1k resistors with a variable resistor
-replace both 1k resistors with diodes

But before I do that I need to try and grasp what's going on here   

I cheated and read a little seems like biasing is the main deal here I'm gonna measure the Vbe on each transistor at present and see what's up

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Hmm this might be over pretty quick

Maybe they are just trying to demonstrate that if you don't have enough forward voltage then stuff isn't gonna work right

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Seems like I remember threads where you were telling the noobies how to adjust the resistors until the notch disappeared

But seems like an elaborate circuit to demonstrate something that simple using two transistors and all.

I guess we'll see what's in store 

The other thing that is messed up is there's no amplification/voltage gain.  I went back and made the volts per division equal for both channels and the output is actually SMALLER 

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Hmm ok yeah I went to tear it down and disconnect and unplug everything I had an idea why not turn up the DC supply voltage so sure enough when i hit about 12.7 V

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And now remeasuring Vbe

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So seems kinda simple oh well 

But I'll go ahead and proceed onward I anticipate they use the variable resistor to obtain needed voltages with the original 8 V DC but the part about the diodes has caught my interest    should be cool