OK, so reading the documentation more, and looking at the .adx file more, when I see something called a Byte string in the .adx file that looks like this:

0xF4 0x57 0x01 0x00 0xB4

I can interpret it as this:

Frame ID=F4
Length=57
Date Bytes=01&00
Checksum=B4

and this would be relatively standard byte string for Mode 1 Message 0 ALDL request

Right ? I think I am beginning to understand more...