I have a DC motor that its specification states that "Electric DC motor manufactured by Buehler. Sinusoidal Encoder Output: 11.5 VAC - 870 Hz @ 12 VDC input. No load speed: 6800 RPM. Runs in either direction"
The motor is connected in a NMOS MOSFET amplifier with 12V on the drain. The tachometer's two terminals are connected to a full-wave bridge rectifier which also has a smoothing circuit using a resistor and a capacitor.
My problem is the output of the bridge rectifier does not change when I change speed of the motor (I am measuring the output voltage of my smoothing circuit)
Does tachometer output value vary respect to its motor's speed ?
Is it possible to convert a motor's tachometer output to DC using a bridge rectifier?
Should my circuit work ?