I was given basically this image:
as a guide and told to build a logarithmic amplifier and verify that its output is proportional to the logarithm of its input. I have a 411 for the op amp, a 10k for the resistor, and a 1N914 for the diode. I'm driving the circuit with a 10khz sine wave, but my output just looks like a square wave. Is this what I'm supposed to get, and if so, how is that proportional to the logarithm of the input? If not, what should I do differently?