Barracuda Legend Kit Problems

[kt315]

in my Bara reaction on metal is in any position of the threshold pot. i also did not tune opamp nulling offset balance pot
and delay preset pot setting them in a middle position. all working without the specs.

[Impulse]

yes but no matter what position the threshold i do not get any change in tone?

[kt315]

the coil hums --->>> hey guys my coil is 10" Dia 20 turns magnet wire 0.5mm 1.7 ohms

[Impulse]

hey guys i have built another board and have managed to get the coil to pick up a gold chain next to the coil i have set pin 6 to 0V again and i have tried to get the tone to change but nothing happens, i have noticed a strange thing the coil hums not the speaker (dont worry i havent connected them the wrong way around) unless i wave a piece of metal infront of it (the coil) and the mosfet gets warmer than i would like

[kt315]

it seems -E is OK. a digital meter gives wrong value if a voltage is not symmetrical and not sinusoidal, on AC range or DC, no difference.
you have not to take attention on those voltages.

[Impulse]

Ok i have taken readings from the 40106 and pin 1,0.55v 2,4.9v 3,0.48v 4,-4.8v 5,0.16v 6,-4.7v 7, -4.9v and pin 14, 0v. i have borrowed an o-scope but it will not turn on atm batt is flat across the coil and 8.3v AC 0.22v DC and now the board does not function at all nothing not a beep unless i pull the power off it and i get a whine as the power drains, nothing changed ?

[kt315]

use my schematic but it maybe not fitted your (silverdog) board.

[kt315]

Ok I will have a look, [ATTACH]35159[/ATTACH] shall I use the batt negative as the main earth point?

your schematic is BBBAAADDD.... DELETE IT AND FORGET. (i had deleted all those schematics drawn by Alex - much mistakes).

[Koala]

Ok I will have a look, [ATTACH]35159[/ATTACH] shall I use the batt negative as the main earth point?

Yes

[Impulse]

Ok I will have a look, shall I use the batt negative as the main earth point?

[kt315]

you must clear see -5V on power pins of 40106: 0 volts on pin 14, -5 volts on pin 7.
reference point measuring is GND ground of the schematic.

[Impulse]

Hi silverdog! i have ordered another kit so i can build a new one then at least i know i have a fresh build i will also take pics as i go and upload them as i have found it hard searching for information and i think it will help anyone in the future with this build, i will check the volts on the 7660 once i get home, if i turn the delay pot from one end to the other i get a 'high' spot in the tone then nothing but if i keep turning i get the 'high' tone again then nothing then after that i do not get any tone so i think i need to take another look in that range but it seemed if i set pin6 to 0V on 5534 with the upper blue pot then turn the delay pot from end to end i do not get anything from the speaker. Tonight i will measure the ac and dc values of the coil also the Volts at pins 8 and 5 for the 7660 .

[silverdog]

What voltage do you have on the 7660 pins 8 and 5 ?

[Old cart]

ok so i have removed the middle resistor and the board says 39k on the middle resistor for the threshold? 39k

OK your board is different than my schematic but that is OK. That is the threshold pot wiper. See my other post for more instructions. Btw what is the value of the restor you installed there, it looks like 390 ohm not 39k .

[Impulse]

ok so i have removed the middle resistor and the board says 39k on the middle resistor for the threshold? 39k