[CW] Exclamation point

[D.J.J. Ring, Jr.]

Commercial working had open and closing parenthesis for as long as I remember.
Starting was KN and closing was KK. I see in WW2 and before they used
KK for both.

I have a copy of McElroy Chart of Codes and Signals in high resolution here:
https://archive.org/details/McElroyChartOfCodesAndSignals

Amateur radio - ARRL - listed KK for both but amateurs never used
exotic punctuation anyway.

73
DR