Lateral CFA 120W - BSA

[dadod]

Ok, i will try

This is going to be ordinary TPC and with lover PM and GM, not my amp any more.

 

[astx]

Your OITPC is unknown to me so it's up to you to provide Thimios a cap/resistor combo to increase the PM/GM for testing.
I'm out.


BR, Toni

 

[thimios]

Let's see how this measured when not oscillate.
Distortion value is close enough to my sound card loop THD.

 

[thimios]

Let's see how this measured when not oscillate.
Distortion value is close enough to my sound card loop THD.

It is late for edit.
Fist photo=2.83v/8R
Second >> =7v/8R
Thrd >> =13v/8R

 

[dadod]

It is late for edit.
Fist photo=2.83v/8R
Second >> =7v/8R
Thrd >> =13v/8R

How you solved oscillation problem?

 

[thimios]

I haven't sometimes not oscillate.
Just now i try using +/-35v and up to now i can, :see any oscillation.....but now i use input signal from a function generator.
Still +/-15 is ok.

 

[thimios]

+/-35v

 

[dadod]

+/-35v

That looks good.

 

[thimios]

That looks good.

I think so too!
Sinusoidal test.
The 47pf is under the board
There also, 1nf from base to gnd at the cascode but i will try to remove as no improvement when testing using +/-50v

 

[dadod]

I think so too!
Sinusoidal test.
The 47pf is under the board

47pF, which one?

 

[thimios]

47pF, which one?

In the feedback C6

 

[thimios]

YouTube
YouTube

 

[thimios]

FFT analyze

+/-35v
idle=130mA
First 1,2,2,4 the sound card loop test.

 

[thimios]

The rest

THD 10khz
THD 20khz
IMD

 

[dadod]

Thank you Thimios for all those measurements.
It's quite close to the simulated values.
Damir

 

[thimios]

Thank you Thimios for all those measurements.
It's quite close to the simulated values.
Damir

Thanks Damir for this excellent amplifier.
Bravo!
Please feel free to ask any other measurement-test.
P.S let me to say thanks to a very good friend from Belgium, who donate me the Laterals.
Thanks xxxx

 

[dadod]

Thanks Damir for this excellent amplifier.
Bravo!
Please feel free to ask any other measurement-test.

What about listening test, I think you said you don't have good enough loudspeakers?

 

[thimios]

What about listening test, I think you said you don't have good enough loudspeakers?

Unfortunately not... and i have one chanel only, up to now.
This was my last piece of duble side photoresist pcb
Listening to one chanel isn't a good practice but those measurements say all the story about what expected.
YouTube

 

[Ampi]

Hi Thimios,
is the problem of the oscillation solved now and what was the reason for that?

 

[thimios]

Hi Thimios,
is the problem of the oscillation solved now and what was the reason for that?

I manage to run this at +/-35v and everything is under control.
May be Damir will find the way to be stable at +/-50v latter.