It's a shame they didn't go for a non-commercial amateur design. They could have used an MK808-DigiLite and had a carousel of test transmissions on an SD card. It would probably have needed some silicone around it to survive the launch though.
Had a very good evening last night - at the last minute I went along to the local radio "what's on your bench" evening and took the RpiDATV and Minituner. I showed it and then proposed it could be a club project as kits and full documentation will be available so everyone should be able to get it working and work someone across town. To my surprise several people came up to me afterwards and said they were very interested and could I give them more details - this really has potential so try and talk to your local club about it....
Re SUP2400 - that's really interesting, will try later and do some measurements such as LO leakage on a standard one and then performance on shifted oscillator. We probably ought to go for a standard crystal such as 8 MHz.
I assumed that the 2400 problem was direct pickup of the SUP-2400 LO by the antenna, because of proximity. It seems to work for Terry.
I kept the modified SUP LO above 2150 to keep it out of the receive band. It has a 2150MHz filter. Maybe that's its purpose.
Freq range as-is can be 2300-2560, you could modify the vco components to shift it lower.....
That gives 9-10MHz crystals as a possibility.
- SUP2400 LO range as standard
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