New bara with no sound. Problem ahead.

[Psyborg]

After changing 10k treshold pot with 50k I have a good possibility of setting treshold. Now my bara in air test detects 1Euro at 15 cm (6 inch). Nice.
Now i need to buy a plastic box to set in bara and battery and make housing for coil.


Thank you all for your help and support.

[Koala]

I try with screwdriver over coil and i have sound only maybe 5 centimeters ( 2 inch) from coil. There is no difference if i turn treshold pot. With delay trim is only worse. I'll make measurements as mohandres recommended in the image which he was uploaded a few posts ago.

offset affects distance as well as coil.

Also a wrongly fitted 2222 will also give low detection. 2N2222 PN2222 P2N222 check the number on the transistor not what you ordered. PN2222 and P2N2222 both plastic have different pin outs

[Psyborg]

I try with screwdriver over coil and i have sound only maybe 5 centimeters ( 2 inch) from coil. There is no difference if i turn treshold pot. With delay trim is only worse. I'll make measurements as mohandres recommended in the image which he was uploaded a few posts ago.

[Koala]

with the TIP127 you can get a little iron discrimination. Was working fine on mine but after messing with differerent coils and settings I have lost it.

Just got mine back running but you beat me. Guess you don't need any measurements

I found trail and error better for the offset adjustment. Maximum depth might not be at the recommended zero volts

[paku]

Good news people! Its working!!
It was problem in 40106. I change also IRF9640 (put a TIP127) and 2n2222 just to be sure . Now need to calibrate.

lol

[Psyborg]

Good news people! Its working!!
It was problem in 40106. I change also IRF9640 (put a TIP127) and 2n2222 just to be sure . Now need to calibrate.

[paku]

I've tried to reverse the buzzer of my bara before and it still give sounds

now you got sound
can you tune the offset to zero
without coil
then put you treshhold to min

[jladre]

I've tried to reverse the buzzer of my bara before and it still give sounds

[mohandes]

hi
i think it help you

[Psyborg]

I check buzzer and polarity is good. I tried it today new LF412 and 7660s. Still nothing. Tomorrow I will try a new 40106.

If it does not work after the new 40106 I will all unsolder and start from scratch.

[paku]

check you buzzer
cos buzzer have polarity + and - from buzzer connect to board

[Psyborg]

Check buzzer. Output A is 4.82V. Output B is 1.46V constant.

[silverdog]

Do you see voltage change at output of Lf412 with metal in coil ?
Piezo buzzer has polarity, check it is connected correctly

[Psyborg]

How to check if 40106 is working?

[Psyborg]

No but do not know what to do so i will change all IC on board. It would be nice if someone described the work of all integrated circuits on board.