On 4/30/07, Rich wrote: > Thank you, Alan. > It is possible to use multiplier circuits and tune to the harmonics. I have > actually done that to 1.2 GHz. The components are actually etched on copper > clad. (Plenty of trial and lots of error) It requires more components and > design effort to get to the waveguide. The beauty of the GUNN Diode is that > it can be placed right into the cavity resonator and directly connected to a > horn. I'm sure you know this frequency will request very high quality microwave guides, with gold plated surfaces and mirror aspect quality. We had used here gunn and impatt diodes up to 10Ghz (Xband) but at 40Ghz, every screw not well screwed or any guide un-homogenity will count... On the other hand, every multiplication will kill the signal integrity, requiring an almost perfect oscillator (talking about phase error) for a reasonable signal to noise ratio after multiplication. I'll like to share your experience here with this experiment (when will be functionally). thx, Vasile -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist