are you using the same pcb layout that is attached in page 1 or you draw your own pcb layout base on the schematic? if you use the attached pcb layout then the position of C4 and R3 is already fixed but in the schematic it is reversed.
you should also check your IC chip if it still good or already busted.
attached image the position of R3 and C4(Ci in the attached image)
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Apex is wrong.
The C3 is shown connected to -IN pin.
Do not connect any capacitor to -IN Pin except if you are a designer applying compensation.
Pin7 is shown grounded.
To unmute you must supply -ve current into pin7.
One cannot do that if it is connected to Signal Ground.
Signal Ground is shown connected to Power Ground.
It works but introduces room for error in output quality.
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A power amplifier generally has no volume adjustment.
The volume adjustment is generally located at the output of the Source feeding the Power Amplifier.
Some will fit a sensitivity pot at the input of a Power Amplifier to allow precise setting of levels. This is a vol pot with restricted range and often linear track instead of audio law.
The volume adjustment is generally located at the output of the Source feeding the Power Amplifier.
Some will fit a sensitivity pot at the input of a Power Amplifier to allow precise setting of levels. This is a vol pot with restricted range and often linear track instead of audio law.
Hello AndrewT
I want to ask simple question the value of C4 is 10uf/16v and C1 & C8 is
220 nf/63v mks .If I use same value cap but higher voltage rating is it make
any difference . because for C4 i am using 10uf/50v and C1& C8 220nf /100v
mks,I am not getting exact volt rating cap .
The brand and build also matter very little.
Make sure your caps are at least a minimum voltage of 125% of the max rail voltage of the power supply. If the power supply is 20v each side then the caps should be a minimum of 25v or else they will explode.
In many cases the capacitance can also be different. If the schematics call for 220uf and you only have 1000uf then try it. If you only have 100uf then just parallel two. Using less capacitance will usually only result in a noisier power supply.
Uriah
I am sorry but you have not provided anyone with much info. My only guess at this moment is that you put the zener diode backward. I am not in a position to check email every day as I am working on my house and searching for a new one but I will try to help and hopefully someone else can help as well. However, with not even a picture you wont get far. A picture needs to be close up, in focus and an appropriate size to post on this forum.
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My lm3886 chips have light grey writing on them so its possibly a fake. component placement looks correct. My concern in the solder spatter. This is everywhere. Especially near pins 1-6 and there is a bug burn mark in the board near 2,4,6. Spattered solder causes arcing/shorting and will kill or temporarily disable an amp. Thats my guess. I always use an awl to scratch away any spatter between traces on my homemade boards.
Nail polish remover often has oil in it and is rather expensive. Just go to any paint or hardware store and get a bottle of acetone. Clean the toner/ink off the board with that before soldering. Either cover the board with spray flux or solder it within a few hours of cleaning, otherwise the copper will oxidize and make soldering harder.
You also need supply decoupling where the power enters the board. 1000 uF where the power comes into the board, 22 uF || 1 uF X7R ceramic right on the pins.
I don't see the point of the two diodes.
~Tom
You also need supply decoupling where the power enters the board. 1000 uF where the power comes into the board, 22 uF || 1 uF X7R ceramic right on the pins.
I don't see the point of the two diodes.
~Tom
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