10-6 Busy, stand by unless urgent or emergency. 10-7 Out of service. 10-13 Advise weather conditions. 10-21 Call this station by telephone. 10-34 Correct time.
All stations stand by for weather report.
10-63 Prepare to make written copy. 10-99 Unable to receive your signals. The alphabet is easily memorized. The phonetic alphabet listed below can be used on the NRAO radio system at the option of the users. Again, their use is optional and if their use does not help or confuses understanding, use plain language.