Creating a Weaver type radio demodulator
Posted: Fri Aug 14, 2020 9:55 am
I am trying to see if I can create a single sideband demodulator for my SDR. I have created an AM demodulator, and a phasing type (all pass networks) single side band demodulator that both work great. An alternative to the phasing demodulator is the Weaver type. I have two audio signals in quadrature(90 deg phase shifted) coming into the FV-1. These signals both need to be band limited with low pass filters to a frequency of approximately 2 kHz, then each signal needs to be multiplied(mixed) one with a sine wave of 2Khz( a little less...below the filter knee) and the other signal with a cosine wave of 2 Khz. Then both multiplied signals are summed at the output. The result is rejection of one of the side bands like you would do with a ring modulator. So my issue is creating the sine/cosine wave at that high a frequency(can't use the LFO's?). I have seen reference to audio test generation with the FV-1 but it is not clear to me if this can be done. Is there a simple approach to creating the higher frequency sine/cosine that will work?