The format is, at best, forgivable. It’s pretty awful. It’s a trip back in time to when Notams were introduced. You might think that was the 1960’s, or the 50’s. In fact, it’s 1924, when 5-bit ITA2 was introduced. The world shifted to ASCII in 1963, bring ing the Upper and Lower case format that every QWERTY key board uses today, but we didn’t follow – nope, we’ll stick with our 1924 format, thank you."
https://web.archive.org/web/20230104130153/https://www.faa.g...
"The FAA is changing the format for Notice to Air Missions (NOTAM) to align with international standards. The transition to the new format will ensure U.S. NOTAMs are compliant with standards set by the International Civil Aviation Organization (ICAO) and promote further global harmonization among neighboring Air Navigation Service Providers (ANSPs)."
ICAO NOTAM format
https://vat-air.dk/files/ICAO%20NOTAM%20format.pdf
Example! (decoder ring not included)
"Q) EGTT/QMRXX/IV/NBO/A/000/999/5129N00028W005"