Kid_TanECE

How low would you want your output level to be?. If you just want it to be a few watts lower, you might experiment a bit with the variable resistor's values that fuction as the gain control. All you have to change is the devices in the final output stage as these usually does the main amplifying. Easy way to do is just lower the max value of the volume control potentiometer by replacing it. I don't know the max current ratings of your devices so if you can experiment it by using a computer based simulator it might be safer. I don't know if this helps just trying my hand at your prob.

:D Looking at the circuits that converts pulse width to voltage. I found that it might be very tasking to implement the circuit as well as finding the neccessary parts. Some devices are not readily available as there are not a lot of experimenters from where I come from. Looking at the catalog of one of our electronics stores, I found that they have an available frequency to voltage IC named the LM2907N. I wonder if it would be feasible If I could connect oscillator output directly to this device so I could use its output to drive my ADC and display? By the way, I changed my capacitance tank design. Instead of making the sides of the tank the conducting plates, I plan to place two copper plates wrapped in insulation(I plan to use two PCBs for my prototype), and place them inside the tank at a few centimeters from each other. I'm thinking I could get a more accurate capacitance with this design. What do you guys think?

Im still a student and my teacher in industrial electronics suggested that I make a precision water container and make the container like a big capacitor with the varying amount of air and water as the container is filled as the dielectric. I am just planning it and I am thinking of using a wein-bridge oscillator with one of the capacitors being the container. The oscillator is then connected to a PWM. In theory, as the container is filled, container capacitance decreases, frequency increases and pulse width is shortened. My problem is that I don't have any idea of converting pulse duration into level indicators. My teacher suggested that I use an averaging amplifier connected to an ADC. Would anybody be kind enough to explain this as I am not yet familiar with analog to digital conversion.