Surf PI help needed.

[endru_star]

Hello everyone .. i 'v got my surf pi 1.2 kit from silverdog, it all looks good and all the pcb and all onboard components looked great... so i did assembled, did my best and tried be very careful and so on.. but all the suddenly when i got to the test point - plug a power and then happen nothing..... no noise or anything at all... a did double check volume and speaker and they are good and connected right, to the board. As i understand it should do some kind of noise even without coil, but i tried both and no luck so far.. i did notes the Q2 - IRF9640 power mosfet gets hot with a coil attached and there is no sound of any kind... so is anybody had a same problem or any ideas what can it be.

[Qiaozhi]

I have had to delete your second post due to an incorrectly attached image. You cannot simply cut-and-paste the image, as the result is a huge list of gobbledygook text.
The correct way to attach an image is to click on the Go Advanced button, and select Manage Attachments.

[endru_star]

OK thanks here is some pic

[endru_star]

also is it any differences between lm358n and lm358ap.. in the part list its a first one but i actually have a lm358AP part... i know its an amplifier an board, and since i don't have any noise could it be a problem?

[daverave]

Hello everyone .. i 'v got my surf pi 1.2 kit from silverdog, it all looks good and all the pcb and all onboard components looked great... so i did assembled, did my best and tried be very careful and so on.. but all the suddenly when i got to the test point - plug a power and then happen nothing..... no noise or anything at all... a did double check volume and speaker and they are good and connected right, to the board. As i understand it should do some kind of noise even without coil, but i tried both and no luck so far.. i did notes the Q2 - IRF9640 power mosfet gets hot with a coil attached and there is no sound of any kind... so is anybody had a same problem or any ideas what can it be.

i have made two surf pi units without too many problems..i would first check for any solder shorts and maybe change the cmos chips which can sometimes cause problems if they have been damaged in some way, cause they are static sensitive.

[silverdog]

Start by checking your voltages
Measure your +5v and -5v supplies on the 7660s IC pins 8 and 5
Also what wire have you used for your coil, what is the diameter and how many turns of wire

[endru_star]

OK, so, on 7660s - #5 is -3.97v and #8 is +4.99v, and the coils i did: first one made with speaker wire 24awg just like says right here: http://www.adrianandgenese.com/blogg...rom-a-diy-kit/, i did 30 turns... and also i did one more with a 0,4mm enameled copper wire, 19 turns, 10".... ever one is not working. Well for right now i need to figure out whats wrong with sound i think, and ill get to coil later..