well here is the story , my brother ask me if I could build a mic . I say sure. he have to do a project for his technology class.
we build a kind of condenser capsule using a chocolate wrapper made of plastic and a film of aluminium (this is a CHHHHHEEEAAAAP mic). is not so thin like a real membrane but it should work.
the back plate is a piece of clean pcb.the distance between the film and the back plate is like 1,2mm and the ratio of the capsule is 3,5cm.
I put 10 9volt bateries for get 80Volts for the capsule. I don`t have 1G resistors so I put 5 of 22M so I have 110M as polarization of the capsule.
as amp I put two 1000 time gain with two op amps(1.000.000 times!!!), we don`t need balanced stuff.the op amp work with another 9v batery.
the problem is that we have VERY low output. I have to normalize the wave to hear something between the noise. it sound clear but with noise I think the signal to noise ratio is catastrofic.
some one have an idea of how improve this mic?
we build a kind of condenser capsule using a chocolate wrapper made of plastic and a film of aluminium (this is a CHHHHHEEEAAAAP mic). is not so thin like a real membrane but it should work.
the back plate is a piece of clean pcb.the distance between the film and the back plate is like 1,2mm and the ratio of the capsule is 3,5cm.
I put 10 9volt bateries for get 80Volts for the capsule. I don`t have 1G resistors so I put 5 of 22M so I have 110M as polarization of the capsule.
as amp I put two 1000 time gain with two op amps(1.000.000 times!!!), we don`t need balanced stuff.the op amp work with another 9v batery.
the problem is that we have VERY low output. I have to normalize the wave to hear something between the noise. it sound clear but with noise I think the signal to noise ratio is catastrofic.
some one have an idea of how improve this mic?