I spent yesterday in a lawyer's office in Washington D.C. for AMSAT and actually enjoyed myself. I followed that with a mad dash back to Trenton to teach the SDR class Frank and I are teaching. Microchip is assisting us beautifully and we have a class full of eager students wanting to take on Suitsat-II and Eagle pieces for their design projects. I apologize for this week being so busy for me that I am unable to jump on to much of the discussions this week on BB and here in Eagle.
Let me dash off some quick comments.
I do not believe we can successfully build the X band component to the modified DCP system. I believe we will be killed by all sorts of LO problems including, but not limited, to phase noise issues. I am already a week behind in delivering Stephensen an analysis of the phase noise on the Class 1 users in SDX, I will add to this a system analysis of the required oscillator performance to use X band in the DCP. Remember, this is a weak signal mode and we are attempting to operate with only a few dB of margin at best. We cannot shed 1 or 2 more in implementation loss (if we are lucky).
I support John's contention that we should choose a band that is currently available world wide for the uplink on which we can feasibly build a system. Pick L or S1 is my recommendation. We chose S1 for all of these reasons.
If you choose L, we can put in two L's or share one with SDX. The antenna is the same required area, but the packing of the antenna on the spacecraft becomes more problematic. I understand Rick's motivation to not get hammered at the annual meeting. Welcome to the presidency. It is not a reason to make a bad choice for the uplink which will kill the utility of the package is my current opinion.
My current vote: stay with what was decided in San Diego or risk L as the primary uplink. I believe that a serious analysis of the impact of trying to get the dual band L/C antenna packed together will be a very illuminating exercise and I believe we will inevitably be led back to the SD decision based on system analysis rather than emotional analysis.
Bob