BARACUDA-Legend-1

[Deghbar613]

i need help
i can't adjust u2 (ne5534) pin 6
here some info
2n2222 base

irf9640 gate

cd40106 pin4

cd40106 pin6 (main simple delay)

cd40106 pin10 (main sample pulse width)

cd40106 pin 8 (Secondary sample delay)

cd40106 pin12 (Secondary sample pulse)

fly back

this video playing in damping resistor
https://www.youtube.com/watch?v=EwLhewp3_fE

THX FOR ANY HELP

[Carl-NC]

You've posted a bunch of waveforms that have nothing to do with U2-pin6. What, exactly, is the problem? You can't adjust the output offset of U2?

[kt315]

was GND clemma of your o-scope probe connected to -12V of a schematic?

[Deghbar613]

You've posted a bunch of waveforms that have nothing to do with U2-pin6. What, exactly, is the problem? You can't adjust the output offset of U2?

yes i am trying to null offset to get 0v.
-1.12v u2 pin6 don't change when turning r6

[Deghbar613]

was GND clemma of your o-scope probe connected to -12V of a schematic?

-12V of a schematic?
or -5v
sorry i didnt understand what you mean

[kt315]

-12V of a schematic?
or -5v
sorry i didnt understand what you mean

then put YOUR schematic here be cause i do not see where you connect (-) probe wire to your board.
2. WHY -5V?

[Deghbar613]

then put YOUR schematic here be cause i do not see where you connect (-) probe wire to your board.

the schematic is geotech rev A
i connect (-) probe to 0v
https://www.geotech1.com/forums/foru...oject-Details=

[GeoMax]

Do you have the correct variable resistor value? And if yes, have you tried another 5534 IC chip? Or maybe you have a Chinese fake IC.

[Deghbar613]

Do you have the correct variable resistor value? And if yes, have you tried another 5534 IC chip? Or maybe you have a Chinese fake IC.

I am trying to get an other ICs maybe it's fake i didn't like outpute wave
so the problem is only from IC or r6 ?

[kt315]

the schematic is geotech rev A
i connect (-) probe to 0v
https://www.geotech1.com/forums/foru...oject-Details=

is your o-scope in OPEN mode of the channel or CLOSE? i do not know how it is tell in English but Carl will help i hope.
anyway, put o-scope probe on -5V and after on +5V and do those pics for me.

[Carl-NC]

It's possible the NE5534 is a fake. Can you post the waveform on pin 6? Also double check the values of R6 and R8, and that R8 has a good connection to +5V.

Here is a more universal method of offset adjustment that will work with any opamp:

[Deghbar613]

It's possible the NE5534 is a fake. Can you post the waveform on pin 6? Also double check the values of R6 and R8, and that R8 has a good connection to +5V.

Here is a more universal method of offset adjustment that will work with any opamp:

This is the waveform of ne5534 pin6 in video below
i am playing in damping resistor
https://www.youtube.com/watch?v=EwLhewp3_fE

[kt315]

the horizontal part of the signal must be sure lie on X axis. is it clear?

[Deghbar613]

the horizontal part of the signal must be sure lie on X axis. is it clear?

Yes
i need to change ne5534 i think it's fake
the others waveform i posted are they ok ?

[Carl-NC]

This is the waveform of ne5534 pin6 in video below

The response decay is way too slow. I suspect a fake opamp.