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[ivconic]

Hi ivica master;
thank you so much.
I add the coil value
[ATTACH]54077[/ATTACH]
[ATTACH]54078[/ATTACH]

I flipped the rx ends,
normal voice.
Grond-disc-sens buttons do not work.
I just came from the workplace, I am starting immediately

Ok, now;
use oscilloscope,
attach probes across TX coil and with trimmer R12 100 ohms ("AMPL." on pcb) adjust TX amplitude and waveform to good sinus and somewhat between 12Vpp to 16Vpp.
First turn DISC potentiometer at "3" or 1/3 of the full turn scale.
Than use piece of mineralized brick, pottery, stone... or (worst solution) very small piece of ferrite and with it swing ~ 5-10cm above the coil and with R16 46k "GEB" trimmer try to adjust no response on it at all.
Situation with GEB is a bit complicated since i added also a trimmer 10K, so you to be able fine to calibrate GEB potentiometer range.
Trimmer R21 10K ("Phase" on pcb) is there to fine readjust phase before switching.
Use different metals and test how it adjusts.
R50 is 180 ohms. When you turn Sense potentiometer R34 1k at maximum sensitivity AND it is still not chattering ; you can lower R50 from 180 to 150 or even 100 ohms.
Experiment.
With Sense potentiometer at maximum sensitivity; it is allowed detector to produce very rare chatters, no problem, normal.
But first of all; i asked you several times and this time i will ask for the very last time;
VOLTAGES? Measure all the power supply voltages and report here!
At LF347 4. pin is Vcc and 11. pin is Vss.
At dual dil-8 opamps 8. pin is Vcc and 4. pin is Vss.
At single opamps 7. pin is Vcc and 4. pin is Vss.
Referent point is ground, when you check voltages at those pins.
Ground is 1. and 2. pin at LM358.
Put "BLACK" probe of voltmeter at 1. and 2. pin of LM358 and with "RED" probe of voltmeter check all the power supply pins i listed above.
If you don't report voltages on your pcb any sooner... i will have nothing else to talk to you.
I horibble dislike to repeat same questions all over again.
Without proper voltages; your detector will never work as it should.
Regards!

[gurdal]

Hi ivica master;
thank you so much.
I add the coil value



I flipped the rx ends,
normal voice.
Grond-disc-sens buttons do not work.
I just came from the workplace, I am starting immediately

[ivconic]

hello my master,
the last situation is as in the video.
other buttons do not work except the volume button.
https://youtu.be/DwWlauSg7OQ

You almost done it!
First of all reverse RX or TX wires, not both.
Double beep response indicates that one of the coil is reversed.
But first tell me the inductances of RX and TX coils, what are those?
BTW speaker is awful, can you replace it with one from broken laptop, or similar?

[gurdal]

hello my master,
the last situation is as in the video.
other buttons do not work except the volume button.

https://youtu.be/DwWlauSg7OQ

[gurdal]

I know I bothered you so much,
I don't know anyone else who can support.

[gurdal]

Hi Master,
I fixed a few mistakes.
ghost voices disappeared.
Tx signal not output.
By the way, apologizing.
Is there a table showing all the 'pins on the chips?
Thanks to you, I am going step by step, we will solve the problem.
thank you very much

[ivconic]

Check the voltages across the supply pins at chips.
Ground are pins 1. and 2. at LM358.
Put black voltmeter probe on it and with red voltmeter probe check all the supply pins at chips.
You must have symmetry in power supply.

[gurdal]

Hi
NE555 4 and 5 pin short circuit burned.
I just installed ne555.
latest case video.

[ivconic]

I may have placed the wrong order,
transistors like this came in.

[ATTACH]54067[/ATTACH]

Check their pinout with instrument.

[gurdal]

I may have placed the wrong order,
transistors like this came in.

[ivconic]

Check the voltages at power supply pins of opamps too.
If some of the transistor type you used is having different pinout; we are in huge problem here!

[ivconic]

I checked again pcb drawing, everything seems correct at that stage.
Only explanation possible is that either you put wrong transistor there or that pinout at some transistor is not matching the data i have.
I would firstly check the pinout and polarity at "BL" transistor. Also check "5C" and "6C".
Here are the markings i added:

[gurdal]

Hello ivica master,
I completed the circuit.
didn't work like bottom versions.
I guess I'm making a mistake somewhere but I couldn't find.
I can't see the signal on the integrated.
this is the last case.
Can you browse if you are available?
Best regards
Gurdal

[ivconic]

Of course, you know; you should put small wires through vias and connect top and bottom layer at those points, right?
Since you done pcb in home made arrangement and holes are not "metalized".
That would be most annoying part of a process.

[ivconic]

some component arrived.
I'll make an in-hole coating with a 0.50 drill bit.
other parts arrive 1-2 days later.
I think I will provide the test within the scope of the weekend pandemic.
[ATTACH]54049[/ATTACH]

Looking forward!
"Bell tone" is switch and not button, just to inform you.
Put double switch to connect 474 at one side and 22pF on another side with their corresponding points on pcb.




"Toprak" is Ground balance.
I understand that!
Thanks to "Muhteşem Yuzyıl" tv series.