Whites Surf PI schematic

[nando.22]

it interferes with the sound of the detector

[bernte_one]

i guess ne555 is for pulse timing

[nando.22]

and which function in the circuit NE555

[nando.22]

I'm having problems with the surf pi not the same sound in speakers

[bernte_one]

That damping resistor might be OK for the coil but the flyback looks like ~70us duration to settle (310us-238us).

Did you have the coil resting near something metallic?

yes i have steel reinforced floor 50cm under coil
thats the common indoor problem i have here

will try it again next weeks in the garden

but thanks for looking

regards

[nando.22]

ihf9640 by replacing one TIP42

[nando.22]

characteristics coil 25 cm and 20 turns of 26AWG wire

[joop]

Can you post pictures of your coil and PCB?

[nando.22]

Oscilloscope not have the sound I hear this low only one speaker when the zumbino approach a metal coil sound disappears.

[homefire]

And what does that mean in English?

[nando.22]

nao tenho osciloscópio o som esta baixo ouço apenas um zumbino no autofalante quando aproximo um metal na bobina o som desaparece

[joop]

Do you have a scope? Did you adjust the offset of the NE5534? You need to give us some more details...

[nando.22]

very low sensitivity also

[nando.22]

completed assembly over the sound is very low

[kt315]

tp - tEST pOINT.