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LM386, LM3916 VU Meter Trouble? Answered

Hey, i have built a VU meter according to an instuctable circuit diagram (https://www.instructables.com/files/orig/FX5/67GS/FLROK12R/FX567GSFLROK12R.gif)
but no matter what, my bar graph stays at 7 bars lit. The LM3916 does not appear to be reponding to the microphone output from the LM386.
any suggestions would be very, VERY much appreciated and my apologies in advance if I have missed any important informaiton.
Thanks

EDIT: the 1uF caps i have on my circuit are polarised, unlike the non-polarised in the circuit diagram, but I am assured by a good friend that it shouldn't make a difference. I am also using the LM386N-3 in case anyone asks!

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user
LED Maestro (author)2013-07-11

apologies to anyone reading this. I rebuilt my board twice and it still wasn't working but i just replaced one of the capacitors and resistors and for some reason it is now working.
Again, thanks for your help.

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mpilchfamily (author)2013-07-11

If i'm not mistaking using an electrolytic cap between the mic and LM386 is causing your problem. That may be blocking the mic's signal from reaching the amp. Put the proper type cap there and then see how it goes.

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user
LED Maestro (author)mpilchfamily2013-07-11

thanks, i will give that ago when I have the part

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user
steveastrouk (author)2013-07-11

Ground pin 5 on the 3916. What happens to the LEDs ?

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user
LED Maestro (author)steveastrouk2013-07-11

pin 5 is grounded and the LED's have gone off but still do not repond to microphone input/LM386 o/p

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