Voice Recorders— A Must for Modern Fire Alarm Communications
IN DAYS gone by, an alarm dispatcher could only shrug and point to his written log or time stamp on the telegraph tape when an irate citizen pointed an accusing finger and said, “I reported the fire at 32nd Street and 10th Avenue, but the firemen didn’t come until 15 minutes later when somebody pulled the fire alarm box.” Now, thanks to the wonders of electronics the dispatcher can flip a switch and let the irate citizen hear his own words distinctly, if excitedly, reporting the fire at “32nd Avenue and 10th Street”—a process that finds the citizen backing apologetically out of the office.
Voice recording, of course, is the answer not only for documentation that provides protection for department personnel, but for keeping a permanent, timed, spoken record of all radio and telephone communications to support the written log. Recordings also help to discipline the use ol air time, and aid in operator training and procedure analysis.
Before the advent of the vacuum tube and more recently the transistor, fire departments depended solely on equipment using a stylus which recorded the intelligence by mechanically impressing the sound waves in a record groove that was played back in the same fashion as an old Victrola. This equipment was tied in with the phone usually reserved for alarms of fire transmitted from sources outside the department and went into operation when the receiver was lifted from its hook. Adequate for its time and purpose, the old recording equipment had the disadvantage of short running time, and had to be operated manually—changing the record—by the operator. No provisions were made to record instructions received from the fire field.
Increase of verbal alarms
With the advent of two-way radio and the telephone fire alarm system and the consequent increase of verbal alarms, instructions and orders, the need for expanded, permanent and automatic recording equipment became urgent and an improved stylustype recording system as well as a magnetic tape recording system was introduced.
The modern stylus-type recorder produces a record which is permanent and which cannot be erased. However a separate machine is necessary for each channel and the running time of the disc or belt on which the messages are recorded is short when compared with most magnetic tapes. Some chiefs prefer the disc or belt style for the ease in which individual instances can be isolated for review, etc.
The core of the magnetic system is a plastic disc or a reel of plastic tape, coated with a metallic substance that permits a magnetic recording to be imposed on it. Run through a recording head that is connected to the radio and telephone receiver and transmitter, the disc or tape makes a permanent recording of all voice communications. This recording can be stored indefinitely, or, once its usefulness is finished, it can be erased and the tape used over and over, depending on its mechanical strength. Tapes for fire department use are generally calibrated in time intervals so that there is an accurate record of the time that alarms and other messages are received. If not calibrated a time announcement is included at the end of the message vocally or automatically.
Except for some variations in size among manufacturers, magnetic recorders generally use this metallic tape. However, the disc type is popular in some departments. One tape type records the information transverse to the longitudinal axis of the tape, somewhat in a zig-zag fashion. The tape for this equipment is fairly wide in relation to a standard tape and a 300 feet reel running at 2 1/2 inches per minute will last for 24 hours.
Photos courtesy the SoundScriber Corp.
The standard tape, generally 1-inch and similar to that used in a home recorder, records on a single, straightline track or area of the tape, and unreels at a speed of either 7 1/2 or 3 3/4 inches per second. However there are recording machines available that will record up to 20 individual tracks on a single tape which eliminates the requirement for having a single machine for each channel desired. Such units can also be set for 24 hours of automatic operation.
Official Columbus F.D. photo by J. Carroll
Photo courtesy the Dictaphone Corp.
Equipment for all types permit monitoring as the information is received, reproducing the exact words being taped. Most have built-in safeguards that prevent accidental erasure of the track. On multitrack tape, one track is usually reserved for time reference signals and any two tracks plus the time signal can be played audibly without interfering with recording of communications on other channels. This playback can be made directly from the tape during recording or from recordings already made.
The New Haven, Conn., Emergency Communications Center employs both the transverse scriber, and a track-type recorder to monitor its telephone reporting alarm system and its radio. The center, established in 1957 and located in the downtown Hall of Records building, is the communications hub for the fire, police and civil defense. Situated in the center is the telephone switchboard and the radio console, manned by three operators around the clock. The switchboard receives all telephone calls from the 415 telephone reporting boxes (372 on New Haven streets and 43 in schools and hospitals), plus all other alarms made from private and public telephones throughout the city and 13 special telephones to ambulance services and utility companies. Beside the special telephone reporting system the center has 14 incoming trunk lines—six for fire emergences and eight for police emergency calls.
All calls are monitored automatically by a transverse recording tape. Two units are used for this purpose while a third is used either as a standby or for playbacks and training. The machines operate unattended 24 hours a day, with the tapes changed at 12:00 midnight each day. Like most units, the recorder is also a reproducer, capable of sound transmission as it is being used, and able to play back its recording at some later time.
Another unit, using the track principle is directly connected to the fire department radio for recording all onthe-air conversation, and placed also beside the operator. The center saves its tapes for approximately a week. if they contain controversial material, however, they are stored indefinitely or until final action is taken. The tapes are then demagnetized for reuse.
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Lieutenant Arthur Jordan, supervisor of the New Haven Emergency Communications Center, says that the effectiveness of the center has l>een achieved by what he terms an educational program. Local media—newspapers, radio and television—continually advise citizens of the alarm reporting system. It is believed that false alarms are minimized because the New Haven population realizes that all telephone conversations are taped. Local publicity is also given to the fact that the recordings have been instrumental in apprehending those persons giving false or misleading information.
The monitors, says Jordan, give the center “an invaluable aid for quick checkback in time of emergency. It is excellent protection for our personnel since we have an accurate record of emergency conversations relating to alanns of fire and to the back-and-forth radio communications between the dispatcher and fire fighting units in the field.” Telephone operators and fire companies know that emergency communications have been recorded and this factor lias protected them in many instances.