NAVY DEPARTMENT,
OFFICE of CHIEF OF NAVAL OPERATIONS,
WASHINGTON 25, D.C., 22 April 1944.

Op-20-F-1/adr
Serial 1411120

1. U.S. Navy Radio Call Sign Book, DNC3(A), will supersede U.S. Navy Call Sign book Part I--Radio Call signs, 1942, DNC3.

2. DNC3(A) will become effective when ordered by the Chief of Naval Operations. The contents of the superseded publication will be destroyed by burning 1 month later. No destruction report is required.

3. Retain the DNC3 binder for use with the new edition. Change the imprint on the binder to agree with the title page. Ships having no binders may obtain them from the nearest issuing office.

4. The distribution of this publication is in accordance with the allowance tables for nonregistered communication publications.

J.V. MURPHY,
Captain, U.S. Navy,
Deputy Director of Naval Communications.

Contents

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Section		Page
1.	Instructions	VII
DECODE
2.	Four-letter pronounceable (except N) calls	2-1
3.	Letter-numeral-letter calls	3-1
4.	Letter-letter-numeral-letter calls	4-1
5.	Three-letter N calls	5-1
6.	Four-lett N calls	6-1
7.	Five-letter N calls	7-1
8.	Local Assignment calls	8-1
9.	Blocks of call signs for assignment to individual aircraft	9-1
ENCODE
10.	Naval activities and administrative organizations except collective and aircraft	10-1
11.	Naval aircraft activities and organizations	11-1
12.	Naval activities and organizations having collective call signs	12-1
13.	Frequently used combinations having special collective call signs	13-1
14.	Geographical list of specific locations	14-1
15.	Geographical list of areas	15-1
16.	Radio Stations--shore, direction-finder, and aviation	16-1
17.	Ships' names (U.S. Navy)	17-1
18.	U.S. Navy ships by classes	18-1
19.	Joint Army-Navy activities	19-1
20.	Allied activities, commanders, and ships	20-1
21.	U.S. Marine Corps	21-1
22.	U.S. Coast Guard	22-1
23.	Call signs for special restricted assignment	23-1