I have my ICAO 24 bit Hex code programmed in the aircraft ELT (Cirrus SR22) and of course, it is also coded in my aircraft Transponder. I will purchase a COSPAS/SARSAT PLB (Personal Locator Beacon) for extra safety as I will be flying over the water.
I can opt for keeping the standard serial number for the PLB (which basically means it will be treated as a personal device, not processed as an aircraft ELT) or code the 24 bit code in the PLB (As of ICAO, this means SAR will consider the distress call as an aircraft call, which is what I want). PLB distributors are used to code marine vessels MMSI identificator in the PLB but know nothing about ICAO Hex code.
In which format should I send them to code the ICAO code in the PLB? Hex? Binary? Octal? i.e.: Hex is 6 char hexadecimal alphanumeric code.