Thought I was starting to understand basic transistor circuits
Someone please assist
Made this circuit on breadboard and jumper wires (problem?) 1khz
Current source at bottom is providing about 2mA...So collector of Q6 should be about 9.8V right? but not the case...Collector is about 11.4V (fluctuates from about 10.45 - 11.6) and my psu is about 11.8v and Q8 needs about 0.6v
The base of Q3 about -0.01v but Q6 about -0.1v... Thinking this was the problem, removed the emitter resistors(to increase gain) and connected 18 ohms between the 2 bases then collector of Q6 became 9.8v like formula will predict...
But I do not want to connect the bases together!! how to fix? I am applying the signal directly to the base of Q6 without capacitor (is this okay?)
After applying signal, the gain changes...it can show gain of 100 (I bypassed R6 and used feedback at this point) now and 2mins later gain reduces or increases...
Thank you! and did not improve push-pull because author wants to show how feedback can improve distortion
I miss this site \
R9 : output resistor is 10k and I used transistor IC
Someone please assist
Made this circuit on breadboard and jumper wires (problem?) 1khz
Current source at bottom is providing about 2mA...So collector of Q6 should be about 9.8V right? but not the case...Collector is about 11.4V (fluctuates from about 10.45 - 11.6) and my psu is about 11.8v and Q8 needs about 0.6v
The base of Q3 about -0.01v but Q6 about -0.1v... Thinking this was the problem, removed the emitter resistors(to increase gain) and connected 18 ohms between the 2 bases then collector of Q6 became 9.8v like formula will predict...
But I do not want to connect the bases together!! how to fix? I am applying the signal directly to the base of Q6 without capacitor (is this okay?)
After applying signal, the gain changes...it can show gain of 100 (I bypassed R6 and used feedback at this point) now and 2mins later gain reduces or increases...
Thank you! and did not improve push-pull because author wants to show how feedback can improve distortion
I miss this site \
R9 : output resistor is 10k and I used transistor IC
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