Please can someone make my day please...Thank you for trying
Where the hell is my mistake!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

The current source is the problem...If to use spice current source it works but now not to use then base of Q1 about 7.5V but it's emitter is about 11.9V same with breadboard measurement

Please!!!!!!!!!!!

V2 is 12V..changed it but no difference..Current source is problem but can not see problem

 

Please can someone make my day please...Thank you for trying
Where the hell is my mistake!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

The current source is the problem...If to use spice current source it works but now not to use then base of Q1 about 7.5V but it's emitter is about 11.9V same with breadboard measurement

Please!!!!!!!!!!!

V2 is 12V..changed it but no difference..Current source is problem but can not see problem

To clarify...want something like this (Although first image, I1 about 100u)

Please someone...No reply before tomorrow : Moderator kindly change my status to "Late Member"

 

Why are you using current-sources in your simulations?
Please use real-world components.

What is this circuit supposed to do?

 

Why are you using current-sources in your simulations?
Please use real-world components.

What is this circuit supposed to do?

it's to amplify but just testing dc points...

yes using transistor for current source but it does not work but it works with "fake current source"

the output with fake source is 6v which is expected but can't get it to work with transistor current source

 

it's to amplify but just testing dc points..

Sorry, but that makes no sense.

the output with fake source is 6v which is expected but can't get it to work with transistor current source

Post the .asc circuit with the transistor current source.

 

Sorry, but that makes no sense.
Post the .asc circuit with the transistor current source.

"Quiescent point"...testing Dc, trying to set output voltage to half supply

There's a mistake but can't see

check voltage on base of Q1 then check it's emitter

 

The schematic looks like this, so obviously there are some parts missing.

And I'm interested in your schematic with transistors, not ideal constant-current sources (which can generate millions of volts), that do not appear in a real circuit.

 

The schematic looks like this, so obviously there are some parts missing.

And I'm interested in your schematic with transistors, not ideal constant-current sources, which do not appear in a real circuit.

View attachment 178866

hmmm..weird..not what i posted...1 min

 

Okay better, but now there's a blank space for constant-current sources.
You said you had some transistor CC sources that didn't work in the circuit.
That's what I want to see.

 

Okay better, but now there's a blank space for constant-current sources.
You said you had some transistor CC sources that didn't work in the circuit.
That's what I want to see.

what??
there's not current source on the left? looks good from my end

 

Okay, I see it now.
All those dangling connections confused me.
If the connection goes nowhere, you should delete them so the schematic is easier to read.

I'll take a look at the circuit.

 

Okay, I see it now.
All those dangling connections confused me.
If the connection goes nowhere, you should delete them so the schematic is easier to read.

I'll take a look at the circuit.

mb...spice has a lot of jumper wires though, he's not complaining

Please take a look ...making it work can get TS out of depression and back to work

 

spice has a lot of jumper wires though, he's not complaining

No, but I am, since I'm the one trying to make sense out of it.

Okay, that circuit is a bit of a mess.
What is the circuit supposed to do exactly?
It doesn't really work to use a current source to bias the collectors of transistors, as you are doing.
You can use them though, to bias the emitters.

 

I'm signing off for the evening.
Be back in the morning (here).

 

No, but I am, since I'm the one trying to make sense out of it.

Okay, that circuit is a bit of a mess.
What is the circuit supposed to do exactly?
It doesn't really work to use a current source to bias the collectors of transistors, as you are doing.
You can use them though, to bias the emitters.

I know, looks messy...Q3 is to sink current from Q2 and Q4 to source to Q1...look at this with the spice current source and signal applied

it can be better (add filter) but note where output starts from (6v)...but I can not make the current source it seems

 

I'm signing off for the evening.
Be back in the morning (here).

zzzzzz...you leave me? what you want me to do? suicide? okay thanks

 

 

Q4 Transistor Your current generator is not working. This transistor provides current to the base of the Q2 transistor. I now, that is not clear. Why do not you enter the whole scheme, but only fragments. If you were not too lazy, then you would see a bad transistor mode.

 

Q4 Transistor Your current generator is not working. This transistor provides current to the base of the Q2 transistor. I now, that is not clear. Why do not you enter the whole scheme, but only fragments. If you were not too lazy, then you would see a bad transistor mode.

Why Q4 not working? Please you can modify current source? also, the other thread : how to get the gain?

Yes you aare right, lazy

 

I'm too lazy to do your work. Make not a fragment of the scheme, but the complete scheme. Then to determine the modes in the points of the scheme, use the analysis of the OP. You see the voltage on my circuits. So I did this analysis.