The schematic for the 4SQRP Freq Mite kit solved a puzzle for me, namely how to boost a small Hi-Z input voltage to a robust 5 volts in order to drive a counter or etc., without loading the source.
Still another puzzle, sort of a flip side problem, is driving me crazy: How does a bench function generator produce a constant voltage at its 50 ohm output over a multi-megahertz range?
For example, if I set the function generator to produce a 500 mV P-P sine wave at 20 KHz, and then twirl the frequency knob up to 10 or 15 or 20 MHz, the output voltage remains constant (within a few %). How is this accomplished?
