EMRFD Message Archive 5348

Message Date From Subject
5348 2010-10-05 07:53:17 Chris Trask Re: [emrfd] Re: X-Môde Mixer
> Is it possible to modify the X mode mixer for base band output for use
> direct conversion or I/Q SDR where DC through say 50khz possible on the IF

Actually, I've been having some problems with the design, most of which
has to do with a faulty offset entry in the spreadsheet I was using. So,
I've gone all the way back to square one with all of this. For the past
couple of days I've been working with a simpler mixer that uses three
transformers and two series-connected diode pairs. It has just 3.50dB of
conversion loss with +7dB of LO power (3.0dB is the theoretical minimum with
ideal diodes) and slightly better IMD than a ring mixer made with the same
parts, both using BAT54S Schottky diodes. It has a zero-IF output, which is
what you are looking for.

I'm about to go the next step with this, using a class 2 (level 10)