ChrioN
Well-known member
I just built a driver for a meter I got. Its like PRRs design ( http://www.electronaut.info/public/PRRMeterAmp_02.gif ) but with some changes.
Instead of using 1Mohm resistors I used 470Kohm, and all the capacitors were 0.1uF. I powered the circuit with a 24vdc wallwart. The opamp is a JRC4556. Oh, and I skipped the 3.6Kohm resistor i serie with the meter.
Now. The meter reacts very differently with different frequencies. When the volume is low, the needle only reacts to bass..
I filmed the meter while I putted a sinustone through it. You can see clearly that the needle goes down when a high frequency is put through it. The mic on the camera is a joke, I don't know what the frequencybandwith is, somewhere between 200hz-10khz.
the clip is roughly 2.2mb
http://hem.bredband.net/b237697/vu.avi
Instead of using 1Mohm resistors I used 470Kohm, and all the capacitors were 0.1uF. I powered the circuit with a 24vdc wallwart. The opamp is a JRC4556. Oh, and I skipped the 3.6Kohm resistor i serie with the meter.
Now. The meter reacts very differently with different frequencies. When the volume is low, the needle only reacts to bass..
I filmed the meter while I putted a sinustone through it. You can see clearly that the needle goes down when a high frequency is put through it. The mic on the camera is a joke, I don't know what the frequencybandwith is, somewhere between 200hz-10khz.
the clip is roughly 2.2mb
http://hem.bredband.net/b237697/vu.avi