Wondering why the DSN is so quiet with only M20 and EMM currently being supported.. Its a long story for twitter limited characters.. but here goes... @HopeMarsMission @NASAPersevere 
The DSN uses a number of data encoding methods, the most common is multi-convolutional 1/2 meaning that for every bit there's an extra bit used for error correction. This extra bit gives us an effective extra 3db on the bit SNR over the symbol SNR.
Cassini came along more than 25 years ago (pre-launch) and wanted a higher level of encoding so JPL built a piece of hardware called the MCD3 which provided the "muscle" not available in software to decode multi-convolutional 1/6 data 1 data bit to 5 error bits...
This increase provided incredibly robust telemetry that could guarantee quality with SNRs of -6db. Literally decoding telemetry with more noise than data. This was so successful that other projects jumped on board with Spitzer and Mars Odyssey 2001 jumping on board...
Fast forward to today.. Each complex have 2 MCD3 boxes, every receiver upgrade in the last 25 years has had to incorporate the MCD3 and its old interface protocols into its design. Currently the only spacecraft using MCD3 is Mars Odyssey 2001... Its holding us back in development
Mars Odyssey does not have the downlink margins to deliver its high rate telemetry using MCD 1/2 so the MCD3 has been sticking around and will officially retire in 2022 at the latest. A new strategy of arraying 2 BWG antenna means we do have the margins for MCD 1/2..
Now that's not as easy as it sounds. Our monitor, control, support product generation and automation is extremely complex and the just "array" it doesn't fit into the current architecture.. This is why we are down currently, we are testing new software that will allow us to do it
Madrid has been excluded from the test because of the importance of @NASAPersevere and @HopeMarsMission approaching the red planet. The old software has just been restored following the test and tracking will resume in 20 minutes... The End
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