Surf PI Pro

[seriall714]

The delay pots dont changes anything on this curve...

I have check two pots and changed 4093 and +5v -5v supply everything normal.

What can cause delay not working??
Thanks

[homefire]

There is no Delay looking at the first Op Amp. You need to move on to the next.

[seriall714]

thanks for answer but also delay pots doesnt change voltage of pin8 of 4093 ?

i check second op-amp output and no signal only 3v arround dc voltage i saw and no curve.

[homefire]

Is there any voltage on pin 8? Maybe the pot is shorted.

[seriall714]

Yes there is 4.7volt at pin 8

And my first opamp curve here



I worked this circuit well half day but little later not worked

[seriall714]

it gives great response to 40x20x20mm neodyum magnet to 30cm clear sound but all metals moneys no answer and as u see in picture upper works on 571 Hz

[Xtrem]

The delay pots dont changes anything on this curve...
[ATTACH]39902[/ATTACH]
I have check two pots and changed 4093 and +5v -5v supply everything normal.

What can cause delay not working??
Thanks

The Curve is ok, but trimm the offset (P1) to set this "line" down to zero volt



Use the second channel of your scope too, first channel to output of first op-amp (pin 6 ne5534)
second channel to pin 3 of U4 , if the time between the 2 points is changing , at trimming the delay pot , then its ok.
Please upload it again here.

[seriall714]

https://youtu.be/2jPStZVC9Js

[seriall714]

Delay pot didn't change anything on both curve

[ionut_mtb]

Delay pot didn't change anything on both curve

use trimmer from pin 1&8 at ne5534 to adjust the 0v offset like Xtrem say first. did you put the right dumping resistor? your delay will not work properly if dumping resistor is not right for the coil u use.

[ionut_mtb]

and i remember one solution which worked for me long time ago:

"I could not get any pulses from Q1 when I first tested it. Somehow R17 and D4, which supply a clock signal to the ICL7660 forced Q1 into saturation. I have removed both components and connected 220 pF from ICL7660 pin 7 to ground. Found this solution in the data sheet."

[seriall714]

My circuit worked when I do first time test for half day. (1euro=18cm) than I remove 1k pot(tlc555) I wanted to put resistor 1k (constant) than its gone it doesn't see anything except Magnets only 1 euro inside of coil maybe 1cm distance...

I tested 0v offset but nothing changed and Henry of coil 300uH 390R2w resistor everything normal.

Can u see in video my 555must be working MOSFET also working look like...only components which is reading money or analysis feedback part of circuit is not working??

Thanks

[seriall714]

Maybe I made short circuit or some weak joint soldering iron but only thing that I need where is problem which IC or transistor or I just burnt diode ?? I checked and changed all IC and 2n3906 ... MOSFET is looks like working normal because it's getting hot little after 2min..

[seriall714]

also i check 2N3906 transistor gives 3.8volt voltage on emiter pin. and on scope i saw pulse of 2N3906.

i still waiting for a miracle for this circuit
thanks

[chemelec]

The Mosfet Should NOT get Hot.
And your Waveform in your Video, does Not look correct.

Maybe I made short circuit or some weak joint soldering iron but only thing that I need where is problem which IC or transistor or I just burnt diode ?? I checked and changed all IC and 2n3906 ... MOSFET is looks like working normal because it's getting hot little after 2min..