Wanted "ADMIRAL"

[CEBRAIL]

httpshttps://youtu.be/qd9Am9hMmeQ?si=jScmYNJGBA4t6PE4

[Deghbar613]

... and here's how my latest PCB works - outside the workshop:

https://www.youtube.com/watch?v=ob1nYn2LGC8

Everithing is still very "raw", but for now I'm happy with the result...

Cheers!

hello gesta and guru
All my attempts are in vain
please share with us your pcb and data maybe some Tips from your experiences
thx

[getsa]

Hello Deghbar613,
I have made the original Admiral (scematic and pcb posted here), as well as variations of the pcb, but the rsults are the same - the quality of the device depends only on the quality of the components used (the ICs and capacitors), and the quality and the right point of ballance of the search head. Also, I am experimenting with the components` values, trying to achieve smoother threshold and testing the behaviour of the device, tinkering it little bit constantly, but the results aren`t significantly better in general.
Have you already repeated the scheme and if so - what specific difficulties did you encounter, so to give you specific advice on its revival and adjustment?
Regards

[Deghbar613]

Hello Deghbar613,
I have made the original Admiral (scematic and pcb posted here), as well as variations of the pcb, but the rsults are the same - the quality of the device depends only on the quality of the components used (the ICs and capacitors), and the quality and the right point of ballance of the search head. Also, I am experimenting with the components` values, trying to achieve smoother threshold and testing the behaviour of the device, tinkering it little bit constantly, but the results aren`t significantly better in general.
Have you already repeated the scheme and if so - what specific difficulties did you encounter, so to give you specific advice on its revival and adjustment?
Regards

THX FOR REPLY GESTA
this some information
Regards
this is my pcb

tx


tl072_pin1 (can't naill it more than that)

cd4053_pin10

cd4053_pin9

tx_data

rx_data

[getsa]

At first glance everithing seem ok, instead the signal on tl072_pin1. There you should have pure sine wave.
Besides - what the signals on pins 4 and 15 /4053 look like? See what I mean on the schematic - TP1 and TP2.
Do you have a constant tone with the threshold potentiometer turned to maximum? - it depends on 100k trim setting.
My version of the board I'm currently playing with is different, but this is for experimentation...

[bonchev2]

Hi getsa, is look you got advice from a old friend I see it and is work perfectly. Greetings!!!

[Deghbar613]

At first glance everithing seem ok, instead the signal on tl072_pin1. There you should have pure sine wave.
Besides - what the signals on pins 4 and 15 /4053 look like? See what I mean on the schematic - TP1 and TP2.
Do you have a constant tone with the threshold potentiometer turned to maximum? - it depends on 100k trim setting.
My version of the board I'm currently playing with is different, but this is for experimentation...

hi getsa thx again and thx too to bonchev2 for videos in youtube i fellow its step by step but finally i need more videos to finish this admiral.i need your experiences ...
gesta i have constant tone with the threshold .
TP1

TP2

no lucky

please any help
Regards

[getsa]

Unfortunately, based on your oscilloscope pictures, captured on tp1 and tp2, I am difficult to define correctly whether there is an objective reason you to unable achieving normal results with this MD (digital oscilloscopes do not quench the return beam, and I cannot estimate your particular setting conditions, based on the picture you posted). First you need to achieve clear sinwave on the first OpAmp. You might over ballanced the coils, trying to get minimal residual voltage. Unballance a bit until before the saturation point is reached and try how it behaves. For the proper schematic reaction and behaviour, you need to make sure by looking at the oscilloscope that the response to the ferrous target is phase, and to non-ferrous target is amplitude (check this on TP1 and TP2).

[Deghbar613]

Unfortunately, based on your oscilloscope pictures, captured on tp1 and tp2, I am difficult to define correctly whether there is an objective reason you to unable achieving normal results with this MD (digital oscilloscopes do not quench the return beam, and I cannot estimate your particular setting conditions, based on the picture you posted). First you need to achieve clear sinwave on the first OpAmp. You might over ballanced the coils, trying to get minimal residual voltage. Unballance a bit until before the saturation point is reached and try how it behaves. For the proper schematic reaction and behaviour, you need to make sure by looking at the oscilloscope that the response to the ferrous target is phase, and to non-ferrous target is amplitude (check this on TP1 and TP2).

thank you gesta , I appreciate your help.
can you share with me some photos from your oscilloscope TP1, TP2, tl072 pin1 to make it as a reference

[Op04]

At first glance everithing seem ok, instead the signal on tl072_pin1. There you should have pure sine wave.
Besides - what the signals on pins 4 and 15 /4053 look like? See what I mean on the schematic - TP1 and TP2.
Do you have a constant tone with the threshold potentiometer turned to maximum? - it depends on 100k trim setting.
My version of the board I'm currently playing with is different, but this is for experimentation...

Dear Getsa,
Thank you for sharing, I saw the video your result is very good,, can you tell us more spesific 140 turn at what diameter? TX RX inductance value? Will you share your current board? many thanks

[getsa]

I intentionally depicted the signals on TP1 and TP2 on the schematic I posted above - if you missed these details just see for reference.
On tl072 pin1 you have to see repeated Tx sine wave, with less amplitude, as a result of the coils ballance.

140 turns are relevant for 28 sm coil plastic shell - it referred to the diameter of the circle/circumference, on which one wind the coils (both coils), and diameter encompassed by the nails you use for frame the windings (for example) need to be 20 sm, so the coil to be accomodated in the shell normally. I haven`t measured the inductance - it depends on several factors. You just need to wind 140 turns on 20 sm blank for winding (same applies to the Tx coil, only need to be wind 60 w), after that the coil need to be tightened with thick thread and tape, as well as to be covered with aluminium foil for shielding (leaving a gap at about 1 sm foil uncovered coil space, avoiding short). Humble, simple, practicle explanation - hope I`ve been of help...
Of course, there are other important subtleties, that might have significant impact on the the overall performance of the device, but it is another story...

[Op04]

I intentionally depicted the signals on TP1 and TP2 on the schematic I posted above - if you missed these details just see for reference.
On tl072 pin1 you have to see repeated Tx sine wave, with less amplitude, as a result of the coils ballance.

140 turns are relevant for 28 sm coil plastic shell - it referred to the diameter of the circle/circumference, on which one wind the coils (both coils), and diameter encompassed by the nails you use for frame the windings (for example) need to be 20 sm, so the coil to be accomodated in the shell normally. I haven`t measured the inductance - it depends on several factors. You just need to wind 140 turns on 20 sm blank for winding (same applies to the Tx coil, only need to be wind 60 w), after that the coil need to be tightened with thick thread and tape, as well as to be covered with aluminium foil for shielding (leaving a gap at about 1 sm foil uncovered coil space, avoiding short). Humble, simple, practicle explanation - hope I`ve been of help...
Of course, there are other important subtleties, that might have significant impact on the the overall performance of the device, but it is another story...

A full detailed answer, I will pay attention to TP1&2. Your explanation will help a lot...many thanks!!

[getsa]

Here you are - my custom PCB, who wants to repeat it and show results here.

[gurdal]

I intentionally depicted the signals on TP1 and TP2 on the schematic I posted above - if you missed these details just see for reference.
On tl072 pin1 you have to see repeated Tx sine wave, with less amplitude, as a result of the coils ballance.

140 turns are relevant for 28 sm coil plastic shell - it referred to the diameter of the circle/circumference, on which one wind the coils (both coils), and diameter encompassed by the nails you use for frame the windings (for example) need to be 20 sm, so the coil to be accomodated in the shell normally. I haven`t measured the inductance - it depends on several factors. You just need to wind 140 turns on 20 sm blank for winding (same applies to the Tx coil, only need to be wind 60 w), after that the coil need to be tightened with thick thread and tape, as well as to be covered with aluminium foil for shielding (leaving a gap at about 1 sm foil uncovered coil space, avoiding short). Humble, simple, practicle explanation - hope I`ve been of help...
Of course, there are other important subtleties, that might have significant impact on the the overall performance of the device, but it is another story...

hello getsa,
What is the coil wire thickness you use for Tx and Rx?
Thank you

[Op04]

Here you are - my custom PCB, who wants to repeat it and show results here.

Thank you