EMRFD Message Archive 14891
Message Date From Subject 14891 2018-06-26 15:25:17 Ravi Miranda Question re SDR schematic Hello,
In the schematic given here: http://dl.btc.pl/kamami_wa/avt2954.pdf
I don't suppose that changing the connections 2B1 - 2B4 around to
facilitate easy routing would be correct? This I assume is necessary
so as to ensure the 0-90-180-270 deg phase are fed correctly to the
opamp.
Not sure hence asking. I've read this:
http://www.wparc.us/presentations/SDR-2-19-2013/Tayloe_mixer_x3a.pdf
I intend to try the circuit to feed S1 and S2 with two out-of-phase
signals from an SI5351. Will the drive from the SI551 need to be
considered? Attenuator perhaps?
Any thoughts will be appreciated.
Best 73
Ravi/M0RVI
--
I'm here to add more value to the world than I'm using up.14892 2018-06-26 15:37:20 Dave Re: Question re SDR schematic Ravi:
Yes, changing the 2B1 thru 2B4 connections will change the 0-90-18-270 phase connections. S1 and S2 need to be 90 degrees apart. If you feed the in phase and out of phase signals from the Si5351 to the clock inputs of the flip flops you will only need a 2X clock.
Dave - WB6DHW
14896 2018-06-29 15:04:10 Ravi Miranda Re: Question re SDR schematic Many Thanks Dave!