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363-131 121-55A 14-.5
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Class Number: 340
Class Title: COMMUNCATIONS: ELECTRICAL
Subclass Subclass
Number Title
850 UNDERWATER
851 .Ship guidance system
852 .Electrodes and electrode systems
853.1 WELLBORE TELEMETERING OR CONTROL (E.G., SUBSURFACE TOOL
GUIDANCE, DATA TRANSFER, ETC.)
853.2 .Diagnostic monitoring or detecting operation of
communications equipment or signal
853.3 .Selective control of subsurface equipment
853.4 ..In horizontal or inclined drilling or passage
853.5 ...Control of drilling apparatus using magnetic field
853.6 ..Control of drill bit or apparatus (e.g., steering, speed,
etc.)
853.7 .Repeater in subsurface link (e.g., cable, etc.)
853.8 .With orientation sensing of subsurface telemetering
equipment (other than drilling equipment)
853.9 .Including detail of subsurface signal storage (e.g.,
memory, recorder, register, etc.)
854.1 .With position or depth recording (e.g., line payout,
equipment locator, etc.)
854.2 ..Location of collar or stuck tool
854.3 .Using a specific transmission medium (e.g., conductive
fluid, annular spacing, etc.)
854.4 ..Drill string or tubing support signal conduction
854.5 ..Wellbore casing or ground
854.6 ..Electromagnetic energy (e.g., radio frequency, etc.)
854.7 ...Optical link (e.g., waveguide, etc.)
854.8 ...Near field coupling (e.g., inductive, capacitive, etc.)
854.9 ..Cable or wire (e.g., conductor as support, etc.)
855.1 ...Coupling connection structural feature
855.2 ...Single conductor cable or wire
855.3 .Multiplexed signals
855.4 .Pulse or digital signal transmission
855.5 ..Digital signal processing in subsurface transmitter
855.6 ...Having acoustic sensor
855.7 .Modification of signal bandwidth, frequency, or circuit
impedance at subsurface location
855.8 .Including specified power transmission feature or source
(e.g., battery, etc.)
855.9 ..Specified alternating current (A.C.) circuit feature
856.1 .In horizontal or inclined passage arrangement
856.2 .With expandable or inflatable sensor element or mounting
856.3 .Including particular sensor
856.4 ..Acoustic or vibratory (e.g., sonic, fluidic, etc.)
870.01 CONTINUOUSLY VARIABLE INDICATING (E.G., TELEMETERING)
870.02 .With meter reading
870.03 ..Having plural transmitters
870.04 .With calibration
870.05 .With calculation
870.06 ..Plural transmitters (e.g., ratio)
870.07 .Combined (TM system with other system)
870.08 ..Radio dial
870.09 ..With alarm or annunciator (concurrent with TM))
870.1 .For radio sonde
870.11 .Plural transmitters
870.12 ..Frequency division multiplex
870.13 ..Time division multiplex
870.14 ...Using particular sync
870.15 ..With plural receiver
870.16 .Condition responsive
870.17 ..Temperature
870.18 .Using a particular modulation (e.g., phase, frequency, or
amplitude)
870.19 ..Pulse
870.2 ...Pulse repetition
870.21 ...Analog to digital function converter
870.22 ...Permutation code
870.23 ...Increase pulses plus decrease pulses
870.24 ...Pulse duration (e.g., pulse train)
870.25 .Phase variation
870.26 .Frequency variation
870.27 .Plural circuits, each for particular magnitude
870.28 .Via radiant energy beam (via particular energy)
870.29 ..Photoelectric cell pickup
870.3 .With particular transmitter (e.g., piezoelectric, dynamo)
870.31 ..Inductive transmitter
870.32 ...Mutual inductance
870.33 ....Flux valve type (e.g., with movable saturating magnet)
870.34 ....Self-synchronous type
870.35 ....Differential type
870.36 .....Linear variable differential transformer (LVDT)
870.37 ..Capacitive transmitter
870.38 ..Resistive transmitter
870.39 .With supply voltage regulation or compensation
870.4 .With particular receiver (e.g., ratiometer)
870.41 ..Plural receivers
870.42 ..With feedback (e.g., reflex along line)
870.43 ...Follow-up (e.g., circuit rebalanced when upset)
870.44 ..With discharge device (e.g., CRT)
901 EXTERNAL CONDITION VEHICLE-MOUNTED INDICATOR OR ALARM
902 .Transmitter in another vehicle (e.g., emergency vehicle)
903 ..Relative distence between vehicles (e.g., collision alert)
904 .Transmitter in one vehicle only
905 .Highway information (e.g., weather, speed limits, etc.)
906 OVERRIDE OF TRAFFIC CONTROL INDICATOR BY COMMAND TRANSMITTER
907 TRAFFIC CONTROL INDICATOR
908 .Portable
908.1 ..Barricade marker
909 .Plural intersections under common central station control
910 ..Central station responsive to traffic detectors
911 ...Central station controls offset (time between beginning of
same phase at adjacent intersections)
912 ..Standby cycling implemented if invalid trasmission received or
loss of transmission occurs
913 ..Offset control
914 ..Split control
915 ..Central station includes display of status of indicators
916 .Intersection normally under local controller
917 ..Controller responsive to traffic detectors
918 ...Controller, when changing right of way, alters or skips
normal "go" cycle of street having no traffic detectedd
919 ...Plural cross highways at intersection each have traffic
detectors
920 ....Density determines split
921 .....Extension of time
922 ...Density determines split
923 ...Extension of time
924 ..Local controller can be superceded by central station
controller
925 ..Pedestrian control
926 ..Manual setting of cycle length and split times
927 ..Rotating cam structure (specific structure required)
928 .Combined (e.g., toll systems, one-way)
929 .Indication of time remaining before change of phase
930 ..Electromechanical movable auxiliary indicator
931 .Traffic control or local controller failure indicator
932 .Pacing (e.g., vehicle keeps pace with sequentially activated
lights)
932.1 .Pivoted
932.2 VEHICLE PARKING INDICATORS
933 VEHICLE DETECTORS
934 .Density
935 .Discriminates vehicle direction
936 .Speed and overspeed
937 .With camera
938 .Compensation for vehicle remaining at sensor position
939 .Environmental or drift compensation
940 .With pneumatic
941 .Inductive
942 .Photoelectric
943 .Sonic or ultrasonic
944 PEDESTRIAN GUIDANCE
945 AIRCRAFT ALARM OR INDICATING SYSTEMS
946 .Nonairplane (e.g., balloon or helicopter)
947 .Land-based landing guidance
948 ..Aircraft actuation of land-based landing guides
949 ..Wind direction
950 ..Movable (e.g., rotatable) guides
951 ..Phased landing guidance (e.g., runway approach, landing,
touchdown)
952 ..Particular energy guide source (e.g., sound, electric field,
radio)
953 ...Visual source
954 ....Alignment of plural sources
955 ....Plural colors
956 ....Modulated light source
957 ...Magnetic field guide
958 .Docking guidance
959 .Takeoff indicator
960 .Landing gear indicator
961 .Potential collision with other aircraft
962 .Icing indicator
963 .Flight alarm
964 ..Phased warnings for same flight condition
965 ..Tactile
966 ..Stall
967 ..Attitude (including yaw, angle of attack, roll, pitch, glide
slope)
968 ..Wind shearr
969 ..Speed
970 ..Altitude
971 .Nonalarm flight indicator
972 ..Runway presentation
973 ..Indicator of at least four flight parameters (altitude, speed,
etc.)
974 ..Attitude
975 ...Roll or pitch
976 ...Glide slope or path
977 ..Altitude
978 ..Speed
979 ..Heading (includes deviation from desired course)
980 ..Indicator visible in pilot's line of sight through windscreen
981 .Aircraft beacons
982 ..Lights communicate (e.g., direction, altitude, reference
position to observer)
983 .Obstruction beacon
984 WATERCRAFT ALARM OR INDICATING SYSTEMS
985 .Navigation guides (e.g., channel lights)
986 .Anchor movement
987 .Rudder position indicator
988 VEHICLE POSITION INDICATION
989 .At remote location
990 ..With map display
991 ..Position indication transmitted by vehicle after receipt of
information from local station
992 ..Position indication transmitted at periodic intervals (e.g.,
distance travelled)
993 ..Position indication transmitted by local station to remote
location
994 ..Vehicle's arrival or expected arrival at remote location along
route indicated at that remote location (e.g., bus arrival
systems)
995 .Map display
996 .Prerecorded message describes position
425.5 LAND VEHICLE ALARMS OR INDICATORS
426 .Of burglary or unauthorized use
427 ..Of motorcycles or bicycles
428 ..Responsive to changes in voltage or current in a vehicle
electrical system
429 ..Responsive to inertia, vibration, or tilt
430 ..With entrance/exit time delay
431 .For trailer
432 .For bicycle
433 .For school bus
434 .For taxi
435 .Of relative distance from an obstacle
436 .Of collision or contact with external object
437 ..Curb
438 .Internal alarm or indicator responsive to a condition of the
vehicle
439 ..Operation efficiency (e.g., engine performance, driver
habits)
440 ..Tilt, imbalance, or overload
441 ..Speed of vehicle, engine, or power train
442 ..Tire deflation or inflation
443 ...By indirect detection means (e.g., height measurement)
444 ....Relative wheel speedd
445 ...With particular telemetric coupling
446 ....Acoustic wave
447 ....Radio wave
448 ....Inductive
449 ..Temperature
450 ..Fluid level
450.1 ...Of hydraulic brake fluid
450.2 ...Of fuel
450.3 ...Of lubricant (e.g., engine oil)
451 ..Fluid pressure
452 ...Of brake fluid
453 ..Brake or clutch condition
454 ...Wear
455 ..Battery charging system condition
456 ..Gear position
457 ..Reminder
457.1 ...Of seat belt application
457.2 ...Of headlight energization
457.3 ...Of parking brake application
457.4 ...Of service interval expiration
458 ..Lamp or lamp circuit condition
459 ..Plural conditions
460 ...With voice warning
461 ...With particular display means
462 ....Digital
463 .External alarm or indicator of movement
464 ..Plural indications (e.g., go, slow, stop)
465 ..Turning or steering
466 ..Speed
467 ..Acceleration or deceleration
468 .External signal light system
469 ..With two or more intensity levels (e.g., day or night)
470 ..Pass - no pass
471 ..Hazard warning or distress signalling
472 ...Auxiliary signal permanently attached to vehicle
473 ...Portable signal
474 ..With audible signal
475 ..Turn signal
476 ...With automatic cancelling
477 ....By predetermined time interval or distance
478 ...With plural bulbs sequentially flashed
479 ..Brake light
480 .Electromagnetically actuated mechanical signal
481 ..Wigwag type
482 ..Normally encased
483 ...Plural concurrent indicators
484 ...Sliding sign or shutter
485 ...Window exhibited sign or shutter
486 ....Drum
487 ..Pivoting
488 ...Multiple indicators
489 ...Three or more positions
490 ....Vertical axis
146.2 DIGITAL COMPARATOR SYSTEMS
500 CONDITION RESPONSIVE INDICATING SYSTEM
501 .With particular system function (e.g., temperature
compensation, calibration)
502 ..Acknowledgementt
503 ...With ringback
504 ..Answer-back
505 ..Interrogator-responder
506 ..Alarm system supervision
507 ...Fail-safe
508 ...Redundant (e.g., added circuit or loop)
509 ...Plural or diverse current sources
510 ...Bridge or potential divider
511 ...Threshold or window (e.g., of analog electrical level)
512 ...Pulse
513 ...Diode
514 ..Testing
515 ...Simulation of condition
516 ...Automatic (e.g., periodic, start-up)
517 ..Selection from a plurality of sensed conditions
518 ...Scanning
519 ...Worst condition
520 ...First sensed exclusively indicated
521 ...Plural diverse conditions
522 ....Combined for response
523 ...Particular sequence of conditions
524 ...Condition position indicator
525 ....Display board
526 ..Predetermined rate of occurrence
527 ..Time delay
528 ...Entrance/exit
529 ...Condition persistence
530 ....Capacitor
531 .With particular coupling link
532 ..Having particular safety function
533 ..Wired
534 ...Coded message
535 ....Mechanical code means (e.g., coded disc)
536 ...Noninterfering
537 ...With impedance level coding
538 ...Combined with power line
539 ..Radio
540 .Specific condition
541 ..Intrusion detection
542 ...Lock
543 ....Permutation
544 ...Disturbance of fluid pressure
545 ...Door or window movement
546 ....Portable
547 ....Magnetic sensor
548 ....Plug or cord tension sensor
549 ....Rotatable sensor
550 ...Partition penetration
551 ...Disturbance of magnetic field
552 ...Disturbance of electromagnetic waves
553 ....Standing waves
554 ....Doppler effect
555 ....Light
556 .....Beam
557 ......Laser
561 ...Disturbance of electric field
562 ....Capacitance
563 .....With bridgee
564 .....Fence
565 ...Responsive to intruder energy
566 ....Vibration
567 ....Electromagnetic energy
568 ..Article placement or removal
569 ...Mailbox
570 ...Drawer
571 ...Alarm on protected article
572 ...Detectable device on protected article
573 ..Human or animal
574 ...Holdup
575 ...Sleep
576 ...Drive capability
577 ..Flame
578 ...By radiant energy
579 ...By ionization or conductivity
580 ..Ice formation
581 ...Thermal
582 ...Vibratory
583 ...Photoelectric
584 ..Thermal
585 ...Refrigerated storage
586 ...Portable
587 ...False alarm resistant
588 ...Time-temperature relationship (e.g., overtemperature exceeds
predetermined interval or time-temperature integral)
589 ....Rate of temperature change
590 ...Fusible, frangible, or destructible sensor
591 ....Containing pressurized fluid
592 ...Expanding fluid sensor
593 ...Switch sensor
594 ....With bimetallic element
595 ...Current modifier or generator
596 ....Cable or elongated probe
597 ....Curie point sensor
598 ....Barrier-layer sensor
599 ....Bridge circuit
600 ..Radiant energy
601 ..Meteorological condition
602 ...Moisture or humidity (e.g., rain)
603 ..Fluent material
604 ...Wetness
605 ...Leakage
606 ...Flow rate
607 ....Filter clogging
608 ....Stoppage
609 ....Counting
610 ....Vane in flow path
611 ....Pressure
612 ...Material level
613 ....Weight in container
614 ....Pressure
615 ....Moving sensor (e.g., impeller)
616 ....Overflow
617 ....Pulverant material (e.g., bin)
618 ....Liquid
619 .....Optical sensor
620 .....Electrode probee
621 .....Having sonic sensor
622 .....Having heat sensor
623 .....Float sensor
624 ......Vertically reciprocable
625 ......Pivoted arm
626 ...Pressure
627 ...Particle suspension in fluid
628 ....Smoke
629 .....Ionization
630 .....Photoelectric
631 ....Lubricant
632 ...Gas
633 ....Catalytic detector
634 ....Semiconductor detector
635 ..Condition of electrical apparatus
636 ...Battery
637 ...Watt-hour meter
638 ...Fuse or circuit breaker
639 ....Plural
640 ...Heater element
641 ...Signalling light element
642 ....Plural bulbs or filaments
643 ....Thermal or magnetic current sensors
644 ...Switch or relay
645 ...Rectifier
646 ...Transformer
647 ...Insulation
648 ...Motor
649 ...Condition of intentional grounding circuit
650 ...Undesired circuit ground or short
651 ....For plural circuit conductors
652 ...Breaking of circuit continuity
653 ...Electronic circuit or component
654 ...Circuit energization
655 ....Heating circuit
656 ....Electrical socket
657 ..Electrical characteristic
658 ...Phase or frequency
659 ...Pulse or surge
660 ...Voltage
661 ....Comparison
662 ....Overvoltage
663 ....Undervoltage
664 ...Current
665 ..Force or stress
666 ...Weight
667 ....On seat
668 ...Tension
669 ..Acceleration
670 ..Velocity
671 ...Angular
672 ....Direction of shaft rotation
673 ..Article transport
674 ...Discrete articles
675 ...Web, film, or strip
676 ....Conveyor belt
677 ...Strand
678 ..Of geometrical gaugee
679 ..Machine condition
680 ...Machine tool
681 ...Synchronization
682 ...Bearing
683 ...Vibration
684 ...Agricultural
685 ...Cranes
686 ..Position responsive
687 ...Connected or disconnected
688 ...Meter dial
689 ...Tilt
690 ...Geophysical (e.g., fault slip)
691 .Specified indicator structure
692 ..Sound reproducer
693 .Specified power supply or housing
825 SELECTIVE
825.01 .Spare channel
825.02 .Tree or cascade
825.03 .Channel selection
826 ..Plural stage matrix system (e.g., path finding)
827 ...Alternate routing
825.04 ..Code or pulse responsive
825.05 .Loop
825.06 .Monitoring and control (e.g., supervisory)
825.07 ..With addressing
825.08 ...Polling or roll call
825.09 ..Quiescent
825.1 ..Scanning
825.11 ...Continuous
825.12 ...Interrupted
825.13 ....Automatic
825.14 ..Synchronization
825.15 ..With storage or recording
825.16 ..Fault condition
825.17 ..With indicator
825.18 ..Relay
825.19 .Communication or control for the handicapped
825.2 .Synchronizing
825.21 ..With addressing
825.22 .Program control
825.23 ..Machine tool
825.24 ..Of audio system
825.25 .Audio system (e.g., by pulse signal)
825.26 .Stock quotation
825.27 ..With information storage
825.28 .Space allocation (e.g., vehicle seat, hotel reservation)
825.29 ..Remote terminal
825.3 .Intelligence comparison
825.31 ..Authorization control (e.g., entry into an area)
825.32 ...With alarm or indication of improper access
825.33 ...Credit
825.34 ..Authentication (e.g., identity)
825.35 ..Commodity (e.g., vending)
825.36 .Having indication or alarm (e.g., location indication)
825.37 ..Additional to other selective control
825.38 ..Party line
825.39 ...Selection by means of frequency
825.4 ...Selector or indicator, per see
825.41 ...Step-by-step impulse
825.42 ....Polarity controlled
825.43 ...Amplitude or polarity controlled
825.44 ..Code responsive (e.g., paging)
825.45 ...Distress signal alarm
825.46 ...Vibratory (tactual) alarm
825.47 ...Group call
825.48 ...Tone code
825.49 ..Location indication
825.5 .Lockout or priority (programmed or variable)
825.51 ..Designated priority
825.52 .Addressing
825.53 ..Plural part (e.g., digit) or repetitions
825.54 .Interrogation response
825.55 ..Printout (e.g., logging) or display
825.56 .With multidigit encoder
825.57 .Pulse responsive actuation
825.58 ..Phase or frequency shift keying
825.59 ..Polarity
825.6 ..Pulse pairs
825.61 ..Having delay line
825.62 ..Serial
825.63 ...Pulse width
825.64 ...Pulse spacing (e.g., pulse repetition rate)
825.65 ...Counting
825.66 ....Relay
825.67 ....Counting chain
825.68 ...Shift register
825.69 ...Radio link
825.7 .Phase responsive actuation
825.71 .Frequency responsive actuation
825.72 ..Wireless link
825.73 ..Plural frequencies
825.74 ...Simultaneous
825.75 ...Permutation
825.76 ...Corresponding to distinct functions
825.77 .Amplitude responsive actuation
825.78 ..Divided resistor
825.79 .Matrix
825.8 ..Plural stage
825.81 ..Electroluminescent elements
825.82 ...Light-emitting diode
825.83 ..Programmable
825.84 ...Having fusible element
825.85 ..Semiconductor crosspoint
825.86 ...Integrated circuit
825.87 ...Logic
825.88 ...Bistable
825.89 ...Switching element
825.9 ...Transistor
825.91 ....Field effect transistor
825.92 ....Four or more elements
825.93 ....Plural
825.94 ...Diodes
825.95 ....Charge storage
825.96 ....Plural diodes at crosspoint
825.97 .Having electron beam device
825.98 .System having rectifierr
286.01 SYSTEMS
286.02 .Network signaling
286.03 ..Speaking tube including circuit
286.04 .Manual alarm telegraph; e.g., other than signal box type
286.05 ..Fire
286.06 .Call station
286.07 ..Hospital
286.08 ..Hotel
286.09 ..Restaurant
286.11 .Annunciator
286.12 ..Drop annunciator
286.13 .Mimic
286.14 ..Mapping
287 .Signal box type (e.g., to call messenger, plural fire alarm
boxes)
288 ..Combined (e.g., alarm circuit over power line)
289 ...With fire extinguisher (e.g., CO2)
290 ...Engine house apparatus controlling (e.g., releases horses,
starts motor)
291 ..Repeaters (e.g., from central to plural fire houses or to
siren)
292 ..Circuit maintenance (e.g., fault alarm, faulty circuit
substitution)
293 ..Variable signal (e.g., police and fire, first and third
alarm)
294 ...Dial selector for variable signal
295 ..Noninterferring (prevents break-in by another box during
transmission)
296 ...Key obstruction type
297 ..With signal at box (e.g., preliminary signal to combat false
alarms)
298 ...Answer back signal acknowledges transmitted signal
299 ...Simultaneous (e.g., actuated by transmitted signal)
300 ...Lamp at box (e.g., to call patrolman)
301 ..Portable box actuating key (e.g., key must be released by
signal from central)
302 ...Frangible guard or protector for key
303 ..Frangible element must be broken to send signal
304 ..False alarm combating (e.g., detention devices)
305 ..Local circuit to actuate box
306 ...Watchman's local circuit
307 ..Transmitters
308 ...Controlled by door of signal box
309 ...With make and break wheel
309.15 .Timer controlled
309.2 ..With nonelectrical indicator or exhibitor
309.3 ..With diversely controlled indicator
309.4 ..Selectively or sequentially actuated indicators
309.5 ...With independent manual controller
309.6 ..Circuit maker-breaker in series
310 R .Combined (e.g., signal over power line)
310 A ..Power
310 CP ..Coupling-plug
311.1 .Paging
313 .Answer back
314 ..Noncorrespondence alarm (e.g., if acknowledgement is
incorrect)
315 .Selsyn typee
316 .Rebalancing at receiver
317 ..Automatic rebalancing
318 .Synchronous distributor at transmitter and receiver
319 .Plural electromagnets or plural motors receiver
320 .Via fluid conduit (e.g., fire hose)
321 .Portable self-contained (e.g., movie usher's signalling
flashlight)
322 .Self-cancelling after fixed time
323 R .Game reporting
323 B ..Bowling
326 .Plural (e.g., concurrent auxiliary) single indications (e.g.,
light flashes when bell rings)
327 ..With sounder signal cut-off
328 .Audible signals (e.g., bell rings softly first and then
loudly)
329 ..Intermittent
330 .In and out indicators (e.g., doorbell button flashes "out"
sign)
331 .Periodic or flashing
332 .Signal light systems
333 .With specific power supply (e.g., power substitution)
425 REPEATER IN UNSPECIFIED TYPE COMMUNICATIONS LINE OR CHANNEL
815.01 VISUAL INDICATOR
815.02 .Three or more messages
815.03 ..Using light-emitting diode
815.04 ..Monogram or character area array
815.05 ...With electromagnetic actuation
815.06 ..Transparent display element
815.07 ...With optical system
815.08 ..Including motor positioner
815.09 ...Having mechanical coupling
815.1 .Multiple color
815.11 .Audio responsive lamp
815.12 .Switchboard or panel type (e.g., bullseye)
815.13 ..Pushbutton
815.14 ..Housing
815.15 .With lamp enclosed in housing
815.16 ..Combined
815.17 ..Light source modifier
815.18 ..Readily movable
815.19 ..Moving light source
815.2 ..Assembly details
815.21 .Concurrent or auxiliary indications
815.22 ..Bell
815.23 .Plural (e.g., grouped drop annunciators with single
restorers)
815.24 .Moving
815.25 ..Semaphore
815.26 ..Rotary
815.27 ..Array or matrix of elements
815.28 ..Circuit closing type
815.29 ..Electromagnet releases latch (e.g., drop annunciator)
815.3 .Self-cancelling after fixed time
815.31 .With light piping
815.32 .False signal prevention (e.g., anti-sunlight)
815.33 .Signal lense
384 R AUDIBLE (E.G., SIMULATED NOISE IN TRAINERS)
385 .Explosivee
386 ..Successive
387 .Weatherproofing
388 .Diaphragm (e.g., horn)
389 ..Phonograph type
390 ..Rotary actuator
391 ..Supports
392 .Percussion-type sound producers (e.g., signal chimes)
393 ..Combined or plural (e.g., manual and electric, bell and
buzzer)
394 ...With unitary battery
395 ..Suspended (e.g., locomotive bell)
396 ..Gong encases striking mechanism
397 ..Polarized
398 ..With linkage between operator and clapper (e.g., church bell)
399 ..Rotary clapper
400 ..Single stroke for single impulse
401 ...Alternating current type
402 ..Details (e.g., clapper)
403 ...Interrupter details
404 .Pneumatic-type sound producer (e.g., horn with electromagnetic
valve)
405 ..Siren
406 ..Whistle
384 E .Electronic
407 MISCELLANEOUS (E.G., TACTUAL SIGNALS)