CW RST Reporting
It is very common to send RST reports in abbreviated form. RST 599 can be sent as 5NN. N is used in place of the number 9.
Another time saver is using a long T in place of the number 0 as in "POWER HR IS 3TT WATTS".
A number code exists for all numbers with N and T codes most common ones. CW stations sometimes report zones as A4 or A5 instead of sending 14 or 15.
1 = A 2 = U 3 = V 4 = 4 5 = E
6 = 6 7 = B 8 =
D 9 = N 0 = T