scope:

- This specification covers self-synchronous order and indicating equipment for transmitting and receiving orders and indications for ship control purposes in Naval ships.

- The types of indicators, transmitters and indicator-transmitters shall be designated in the following form, as applicable (see 6.1):

- The basic indicator for ship control order and indicating equipment is IC/.

- The types and quantities of synchro receivers and synchro transmitters contained in the component shall be designated by a number symbol as shown in table I.

- The type of mounting and construction (see 6.1) of the enclosure shall be designated by a single letter as shown in table II. Table II - Enclosure, mounting and construction.

Symbol Mounting Construction ------------------------------------------------ B Bulkhead Cast P Panel Cast S Pedestal Cast U Universal Cast D Deck Sheet metal W Bulkhead Sheet metal X Panel Sheet metal Y Pedestal Sheet metal Z Universal Sheet metal Note. - Cast enclosures are normally aluminum, except for rudder angle transmitters, bow plane angle transmit- ters, and stem plane angle transmitters which are bronze. Sheet metal enclosures are normally made of sheet brass, except where material scarcity compels the use of sheet steel.

- The characteristics of dial size, dial illumination and power frequency of the component shall be designated by a single letter as shown in table III. Table III - Dial size, dial illumination and power frequency.

Dial Power Symbol Dial size illumination frequency ----------------------------------------------------------- Cycles A 4 inch diameter yes 60 B 6 inch diameter yes 60 C Special yes 60 D 4 inch diameter no 60 E 6 inch diameter no 60 F Special no 60 G No dial no 60 H 4 inch diameter yes 400 I 6 inch diameter yes 400 J Special yes 400 K 4 inch diameter no 400 L 6 inch diameter no 400 M Special no 400 N No dial no 400 Note. - Special dials include the following typical examples: (a) 8 inch diameter dials for pedestal mounted engine order indicator-transmitters. (b) 5 inch diameter dials for special compact engine order indicator-transmitters, and windows for observation of a selected section of propeller order dials.

- Special or additional features shall be designated by a number ranging from 01 through 99, reserved for this purpose as shown in table IV. Table IV is applicable to all indicators, transmitters, and indicator-transmitters.

- The number indicating the special, or additional, features shall be followed by a dash and a number indicating the manufacturer. This number will be assigned by the bureau or agency concerned at the time of action on drawings of the component.