Hi John,
Nice drawing, and much more complete than my "sketch" hi..
One question...
Was the L.O. using 74AC74 + 74AC08 better than the simple 74 HC 107 method ?
...and one suggestion:
To eliminate the need to adjust the offset voltage for the 4 input
opamps, simply use AC-coupling. I found this very cute to reduce the
number of trimpots to the minimum (namely zero). The TL084 which I used
had an output offset error near 7 mV, the AC coupling (0.22 uF) between
the OPAMP output and mixer input completely eliminates this. The 2.5 V
bias for the switches was provided with a simple voltage divider from
the 5 V supply.
So much for today, further experiments will follow soon.
Regards,
Wolf DL4YHF .
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