Part of my design does incorporate filters before this rectifying stage, but that's mainly because the 200Khz signal has to be extracted from a 50HZ mains AC waveform before it can be processed. By the time it reaches this rectification stage, all I really need to be able to do is detect is the presense or absense of the waveform and provide this information, in TTL form, to a microcontroller. I don't need to maintain accurate reproduction of the 200Khz signal, I only need to be able to detect the presense of it.
With that in mind, I'll need a buffer stage perhaps of the schmitt trigger type after the rectification stage, in order that the correct DC levels for logic 1 and logic 0 are provided to the microcontroller.
Thanks for the reply red.
Brian