Why amateur radio operators say “73”

Posted By on January 18, 2014

telegraphoperatorThose who spend any amount of time listening to amateur radio hear operators closing their exchanges with a polite and concise “73” meaning “best regards” … but where did it come from?

From what I’ve read, it goes back to a convention in 1859 where telegraph operators discussed saving “line time” by devising a code that would reduce the number of characters for standard expressions. Twenty years after the the convention, Walter Phillips, created a list of shorthand codes and it became the Phillips Code. The number portion of the codes were called “Wire Signals” and a few remain with us today.

Here’s one of the shorthand abbreviations that I found particularly interesting:

“The terms POTUS and SCOTUS originated in the code and entered common parlance when newsgathering services (in particular the Associated Press) adopted the terminology.”

The numeric code is a small part of the abbreviations outlined in the Phillips Code (developed by telegrapher Walter P. Phillips). Here are the numbers as referenced:


WIRE Preference over everything except 95

1- Wait a moment

2- Important Business

3- What time is it?

4- Where shall I go ahead?

5- Have you business for me?

6- I am ready

7- Are you ready?

8- Close your key; circuit is busy

9- Close your key for priority business (Wire chief, dispatcher, etc)

10- Keep this circuit closed

12- Do you understand?

13- I understand

14- What is the weather?

15- For you and other to copy

17- Lightning here

18- What is the trouble?

19- Form 19 train order

21- Stop for a meal

22- Wire test

23- All copy

24- Repeat this back

25- Busy on another wire

26- Put on ground wire

27- Priority, very important

28- Do you get my writing?

29- Private, deliver in sealed envelope

30- No more (end)

31- Form 31 train order

32- I understand that I am to …

33- Car report (Also, answer is paid for)

34- Message for all officers

35- You may use my signal to answer this

37- Diversion (Also, inform all interested)

39- Important, with priority on thru wire (Also, sleep-car report)

44- Answer promptly by wire

73- Best regards

88- Love and kisses

91- Superintendent’s signal

92- Deliver promptly

93- Vice President and General Manager’s signals

95- President’s signal

134- Who is at the key?

See full Phillip Code at Radions.net

– 30


Desultory - des-uhl-tawr-ee, -tohr-ee

  1. lacking in consistency, constancy, or visible order, disconnected; fitful: desultory conversation.
  2. digressing from or unconnected with the main subject; random: a desultory remark.
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