Pinpointer with discrimination "Cat-FM" on ATMega328P

[void118]

with detached buzzer 28ma without detection
30.5ma with detection
with connected buzzer 700ma without detection
800ma with detection

the buzzer on the capacitor marks me 47uf and 45 ohm on resistance

however the buzzer is passive, powering it directly does not emit any sound

First, passive piezo buzzer Is equal to capacitor and It can't pass constant current!, It's not piezo buzzer.
My passive piezo buzzer has 10nF capacitance and has endless resistance.

Second, 28mA without detection Is too much, check your schematic please, I mean MCU consumption(~15mA), generator consumption(500uA).

Third, disconnect the base of sound transistor from MCU and check current again, may be you have deffect transistor too.

Show me your buzzer please)

[void118]

It seems to me that you have electromagnetic speaker that just looks like buzzer, and because reactive resinstance on sound frequency Is lower thar active resistance you see such consupmtion.
But anyway, 28mA In standby mode Is too much.

[useus]

the buzzer is pac-1205

[useus]

with base of transistor disconnected and buzzer connected 15.6ma


now the buzzer does not emit background noises as it did before

[void118]

the buzzer is pac-1205

PAC-1205 It't not piezo buzzer, It Is electromagnetic transducer with 6V max. supply, It Is first, and second when you detouch base transistor from sound I see normal consumption.
Conclusion - you have misstake with your sound transistor connection or It's not working properly. Check your transistor please, see In attachment.
Connect emmiter to 5V Instead battery, remove 1K parallel resistor from your transducer.

I hope you are using BC557 In the sound circuit?

[void118]

[useus]

PAC-1205 It't not piezo buzzer, It Is electromagnetic transducer with 6V max. supply, It Is first, and second when you detouch base transistor from sound I see normal consumption.
Conclusion - you have misstake with your sound transistor connection or It's not working properly. Check your transistor please, see In attachment.
Connect emmiter to 5V Instead battery, remove 1K parallel resistor from your transducer.
[ATTACH]55238[/ATTACH]
I hope you are using BC557 In the sound circuit?

i use bc557 and i tried another one with the same result, now i try to connect emitter to + 5v, i will let you know if i solve, pac 1205 i was convinced it worked at 1 also at 12v, i had read it somewhere

[void118]

i use bc557 and i tried another one with the same result, now i try to connect emitter to + 5v, i will let you know if i solve, pac 1205 i was convinced it worked at 1 also at 12v, i had read it somewhere

Ok, just check your BC557 with multimeter, but such consuption Is abnormal, look, I found datasheet for your tranducer:
http://www.fastelettronica.com/PAC_BUZZER.pdf

[void118]

12V Is too much for It (twice) and It has big coil resistance, try connect In series to him 1k resistor please.
But first check your BC557 with multimeter please.

[void118]

BC557 max. collector currend Is 200mA, of course It will heating up!
It will work nice In generator but with such tranducer we should limit collector current to 30-40mA by placing current limit resistor In series.

[useus]

I solved it, thanks for the help, all because I had read an incorrect buzzer data sheet.
bc557 works
i connected emitter to 5v, direct base to atmega without 1k
now the buzzer sounds loud and does not heat up


consumption 28ma without detection
56ma with detection

I think the higher consumption is due to the lower voltage
thanks again for the help

I just need to make a small change on the board and I'm good to go

[void118]

I solved it, thanks for the help, all because I had read an incorrect buzzer data sheet.
bc557 works
direct base to atmega without 1k

I'm sure base resistor Is must be In the base to limit base current, place at least 470 Ohm to the base please)

[useus]

I'm sure base resistor Is must be In the base to limit base current, place at least 470 Ohm to the base please)

sorry I'm confused, I wanted to write that I removed the resistance in parallel to the buzzer.
I went haywire to solve the problem, luckily there is you!

the sensitivity setting is interesting, but I think it can be improved.


I was just trying, between the lowest and highest sensitivity level there are a few mm of detection.


maybe it is also due to the type of coil, mine is 2.24mh

edit: I also solved the consumption, 15.7ma without detection and 27ma with detection

[void118]

sorry I'm confused, I wanted to write that I removed the resistance in parallel to the buzzer.
I went haywire to solve the problem, luckily there is you!

the sensitivity setting is interesting, but I think it can be improved.


I was just trying, between the lowest and highest sensitivity level there are a few mm of detection.


maybe it is also due to the type of coil, mine is 2.24mh

Yes, you are right, I will Improve It In the next version I think I will post It within one-two hours.

[useus]

another tip is if possible to improve stability, after detection, when the object is moved away, it is often necessary to recalibrate because it continues to sound

(I make you fatigued LOL)