OPERATING PROCEDURES.

TM5--4210-224-14&P

2-13. OPERATION OF SIREN/PUBLIC ADDRESS SYSTEM (Continued).

For siren operation, select desired tone on selector switch (3, figure 2-4). The selecto switch has six

positions:

(1)

PA Allows operation of the public address system through the common microphone. When the switch

is in this position, the red pilot LED (2, figure 2-4) is illuminated.

(2)

RADIO In this position, incoming radio messages are amplified by the siren and rebroadcast over the

external speaker. Siren tones (WAIL, YELP, HI-LO) do not operate in this position.

(3)

STANDBY In this position, it is possible to operate the siren by activating the manual pushbutton or

mechanical siren foot switch. A WAIL tone will be produced using either the manual pushbutton or

mechanical foot switch.

(4)

WAIL In this position, the siren produces a continuous WAILING sound up and down in frequency.

Depressing the manual pushbutton will produce the YELP tone.

(5)

YELP In this position, a continuous rapid "warbled" tone is generated.

Depressing the manual

pushbutton will have no effect.

(6)

HI-LO In this position, a two-tone sound will be heard. Depressing the manual pushbutton will produce

the YELP tone.

The Manual Pushbutton (1, figure 2-4) operates the electronic siren in the manual operation mode. The push

button has no effect when the selector switch (3) is in RADIO.

(1)

It produces the WAIL tone when the selector switch is in STANDBY.

(2)

It produces the YELP tone when the selector switch is in WAIL.

(3)

It has no effect when the selector switch is in YELP.

(4)

It produces the YELP tone when the selector switch is in HI-LO.

(5)

A mechanical siren foot switch can also be used for the above modes when the vehicle is in motion.

2-14. OPERATING PROCEDURES.

The following paragraphs will describe operating procedures necessary for all basic firefighting missions for which

the firefighting truck was designed.

2-46