I have watched the comments about 2m operation and wonder if there are some other possible solutions? The multiplexer/ switching mixer chip is not fast enough for 144Mhz mixing but diode ring mixers are readily available at that frequency. So then to generating the quadrature LO at 144Mhz....its a bit fast for easy logic....but if you used the standard quad circuit used at hf and mixed I and Q up in phase you would generate a 144MHz quadrature LO signal. The problem is obviously the extra mixing stage and birdies but these should be easy to avail and the second mixer could be used to sweep the signal over a wider portion of the band (DDS??) the alternativeis to mix down and then do the quadrature bit, which might be a lower parts count. I have no idea which would work out best though.....any ideas if a "direct conversion" 2m RX would be worth doing like that?? I suspect the "IF" vesion with some IF gain would be perhaps better.
Alan G3NYK
