The binocular - multi aperature core - DBM is the cat's meow!
I put these two on a board with a diode ring and found signals all over the bands. I am listening to a couple of hams on 80 meter SSB as I write this.I need more than one test but it is doing better than anything I've tried lately. I'm using my signal generator to drive it and the tuning is touchy. With a good VFO this should be my final DBM. So next I try Andy's oscillator. I have bread boarded a couple and it worked. Now for a permanent build of the oscillator.
I will try the smaller core later.