I look forward to seeing some Tulsa action on the site for sure and congrads on getting it working. Great place to feed for sure.
As for ADFB2C most the hex codes I have received around it are a mystery as well. The last US civilian aircraft hex code is ADF7C7 which would relate to aircraft registration N99999. Past that I have some ground and Mode-S call test codes and your Tulsa hex code is in the middle of that bunch. Some of these codes are for ground units at selected airports for sure. Others, well I just don't know. My guess is that this area of US hex codes are assigned for civilian use since my first known US military hex code starts at ADFC00.
Those mystery codes between the end of the civ aircraft block and the beginning of the known DoD aircraft block are
ADF7ED
ADF8C1 Reporting FL900
ADF97F
ADF991 (Grnd Unit with Test 1234 in call block)
ADF992 (Grnd Unit with Test 1234 in call block)
ADF993 (Grnd Unit with Test 1234 in call block)
ADF994 (Grnd Unit with Test 1234 in call block)
ADFA21
ADFA39
ADFA69
ADFABD Reporting FL800
ADFB2C Your TUL hex code reporting FL800
ADFBDD (Grnd Unit with Test 1234 in call block)
ADFBDE (Grnd Unit with Test 1234 in call block)
ADFBDF (Grnd Unit with Test 1234 in call block)
ADFBE0 (Grnd Unit with Test 1234 in call block)
ADFBF4 (Grnd Unit with Test 1234 in call block)
ADFBF5 (Grnd Unit with Test 1234 in call block)
Just wondering out loud (as I often do) since some of these things do not appear to be moving, I wonder if some of these hex codes are for static high altitude balloons. I'm not saying that there aren't any fed/gov hex codes in this ADF7C8-ADFBFF block, I just haven't found any yet that I can confirm.
Good hunting de Larry