Background A little after 1600 UTC on February 21, 2010, in the #wunclub IRC channel, a user (LDO, a European region monitor) threw out the question "Vietnamese numbers? 10255" I had been paying fairly close attention to the Asian numbers stations for the past year or so, and immediately tuned to the indicated frequency of 10255 kHz. Sure enough, there was a previously unreported Vietnamese language numbers station on that frequency. S6 or stronger here in Southern California. What made this signal fairly interesting is that as far as I know no Vietnamese numbers station of any kind had been...