he LM358 operational ampifier module is a general purpose single-channel amplifier with adjustable gain. PACKAGE INCLUDES: LM358 Operational Amplifier Module KEY FEATURES OF LM358 OPERATIONAL AMPLIFIER MODULE: Adjustable gain up to 100x Gain adjustment pot 1 Channel Frequencies up to 700kHz 3-32V operation The LM358 operational amplifier module is handy for providing basic waveform amplification in a project such as boosting a signal from a microphone. The gain has a range of 1x to 100x and is adjustable using the multi-turn potentiometer on the module.  Turning the pot CW lowers the amplification while turning it CCW increases it. An power LED is included on the module. OUR EVALUATION RESULTS: These assemblies work quite well at basic amplification tasks when dealing with moderate frequency signals like microphone inputs.  With a 10mV 1KHz input, we were able to adjust over the full range of 10mV to 1V on the output without significant distortion. Note that though the LM358 can handle up to 32V, the LED has a 1K current limiting resistor, so at about 22V, the LED will be driven at its maximum current of 20mA.  The LED can be removed if using the module at higher voltages, or the 1K resistor at R10 can be replaced with something bigger like a 2.2K or 4.7K.