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still looking for help i have replaced the resistor 100k for the recomended 100 ohm but i still have no sound. i have a scope and seem to get a signal on T1 & T2. please help as im stuck in limbo.
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noooob i need of help
As requested by some guys here I have taken some pics, can anyone spot anything i have cocked up so badly IE that i cant see it
pic's 1.2 3& 4 board
pics 5 & 6 scope signals from TP1
pics 7& 8 scope signals from TP2Comment
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FET backwards
Hi Langleylocator,
looking at your board pics, it looks like your FET (irf9640) is backwards or 180 degrees, you should have it so it looks like the one in the image below.
correct
Yours
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Wow thanks for the quick reply i was not sure when i places it on the board i only saw the "S" and followed that pin lay out, will re solder back in the other way round. Have to take the kids to soccer now will report back when done .
thanks again !Comment
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sure Q2 is wrong way
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Your welcome Langleylocator....
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Hi guys, thanks for all of the replies, However still no luck,and no sound( apart from a faint buzzing from the mosfet hope i haven't cooked it)
here is a photo. still not certain if it is the right way round though? also seem to have the very simillar voltage on the S & G Pins is this normal ?Comment
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Can you repost the image a little smaller or from a bit farther away, the pic is so large it is hard to see what's what..Comment
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hi, working on that now
here is the fet cropped.but for some reason it keeps blowing it up to fill the page you can see the pins marked s 0 And A triangle on the fet but on the silk screen it seems to suggest it should be the other way around.Comment
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Just make sure it has the writing facing up with the drain sink laying against the board like in this image.
http://www.geotech1.com/forums/attac...0&d=1403273753
Check Q6 and R34 along with your solder joints over the whole board. I believe R34/Q6 controls your audio so make sure R34 value is correct and
then check the transistor, if I remember correctly it should be the MPSA13.Comment
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Originally posted by langleylocator View Post
The "S" you're showing appears to be the Siliconix logo and should not be confused with a source pin designation.Comment
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thanks guys another step nearer it looks as though we have some kind of life attached pic is on the scope from TP1. I have had the tester on the MPS A13 and have 12.46 on the collector 0 volts on the base and the emitter am i correct in guessing that this is not right and the transistor is Kaput defunct let out the magic smoke.
pic quality is also better used image re-sizer to make it fit better please let me know what you think thanks again for all of your help,Steve.Comment
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