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Class Number: 379
Class Title: TELEPHONIC COMMUNICATIONS
Subclass Subclass
Number Title
1 DIAGNOSTIC TESTING, MALFUNCTION INDICATION, OR ELECTRICAL
CONDITION MEASUREMENT
2 .Including fault responsive disconnection of tested component
3 .Of hybrid, or echo suppressor or canceller
4 .Of repeater
5 .By loopback
6 .By analysis of injected tone signal
7 .For detection of eavesdropping device
8 .With blocking of normal usage
9 .Of centralized switching system
10 ..By automatic testing sequence (e.g., programmable, scanning)
11 ...Routiner
12 ..With dedicated testing line or trunk
13 ..Of call timing or charging equiment
14 ..Of plural exchange network
15 ..Of automatic switching equipment
16 ...Of switching path
17 ...Of switching selector
18 ...By use of call address signal
19 ...Rapid manual connecting structure for test equipment
20 ..Of switchboard element condition (e.g., lamp)
21 .Using portable test set (e.g., handset type)
22 .Of trunk or long line
23 ..Of line signalling
24 ..Electrical parameter measurement (e.g., attenuation)
25 ..Conductor identification or location
26 ..Fault detection or location (e.g., continuity, leakage)
27 .Of subscriber loop or terminal
28 ..Of data transmission instrument
29 ..Terminal arrangement to enable remote testing (e.g., testing
interface)
30 ..Loop impedance (e.g., resistance, capacitance)
31 ..Of line signalling generator (e.g., dial, tone code
generator)
32 .Indication of nonstandard condition of telephone equipment
33 ..Alarm or emergency (e.g., cut line)
34 SERVICE MONITORING OR OBSERVATION
35 .Listening-in or eavesdropping type
36 FREE CALLING FROM PAYSTATION
37 EMERGENCY OR ALARM COMMUNICATIONS (E.G., WATCHMAN'S CIRCUIT)
38 .Personal monitoring (e.g., for the ill or infirm)
39 .Responsive to sensed nonsystem condition
40 ..Automatic dialing
41 ..Transmission of recorded audio message
42 ..Plural conditions
43 ..Fire
44 ..Intrusion
45 .Central office responsive to emergency call or alarm (e.g.,
"911", operator position display)
46 .Called line or station condition responsive (e.g., recall if
busy)
47 .Plural alarms over single linee
48 .Announcement or alarm received at terminal station (e.g.,
"butt-in", alarm)
49 .Central station with plural substations
50 .By pulse or digital signal
51 .With automatic dialing or transmission of recorded audio
message
52 INCLUDING AID FOR HANDICAPPED USER (E.G., VISUAL, TACTILE,
HEARING AID COUPLING)
53 WITH CONVERSATIONAL VIDEO COMMUNICATION (I.E., VIDEOPHONE)
54 .Switching control
55 HAVING NEAR FIELD LINK (E.G., CAPACITIVE, INDUCTIVE)
56 HAVING ELECTROMAGNETIC LINK FOR SPEECH OR PAGING SIGNAL (E.G.,
LIGHT WAVE LINK)
57 .Control of selectively responsive paging arrangement over
telephone line
58 .Radio telephone system or instrument
59 ..Zoned or cellular system
60 ...Having zoned/cellular system switching (e.g., handoff)
61 ..Including cordless extension set (i.e., having single
subscriber line access)
62 ...With privacy or lockout (e.g., identity verification)
63 ..Including supervisory or control signalling
64 HAVING SINGLE CHANNEL TELEPHONE CARRIER
65 .Including call signalling (e.g., ringing, off-hook, dialing)
66 .Over power line
67 WITH AUDIO MESSAGE STORAGE OR RETRIEVAL
68 .Dynamic audio signal recording or reproduction
69 ..Call originating
70 ..Call intercept or answering
71 ...Consecutive use of recorded phrases or words to form message
72 ...Sequential or repeated announcement during single call
initiated cycle
73 ...Plural record carrier channels
74 ...Remote control over telephone line
75 ....Remote dictation
76 ....Announcement selection or replacement
77 ....Control by generated tone
78 ...Acoustic coupling
79 ...With specified call initiated cycle control circuitry
80 ....Voice signal presence responsive
81 ....Call termination responsive (e.g., hang-up)
82 ....Having specified call initiation (e.g., ringing) responsive
circuitry
83 ....Structural detail of storage medium drive
84 ...At switching facility (e.g., central office, switchboard)
85 ..Recording of telephone signal during normal operation
86 ...Inductive pickup
87 ..Reproduced signal distributed over telephone line
88 .Stored in digital form
89 ..Subscriber control of central office message storage or
retrieval
90 TELEPHONE LINE OR SYSTEM COMBINED WITH DIVERSE ELECTRICAL SYSTEM
OR SIGNALLING (E.G., COMPOSITE)
91 .Credit authorization
92 .Polling (e.g., audience survey)
93 .With transmission of a digital message signal over a telephone
line
94 ..Including switching stationn
95 ..Access restricting
96 ..Including terminal for display of digital information
97 ..By voice frequency signal (e.g., tone code)
98 ...By modulated audio tone
99 ...Having acoustic link
100 .To produce visual-graphic copy reproduction (e.g., facsimile)
101 .Audio program distribution
102 .Remote control
103 ..Of entrance or exit lock
104 ..With indication
105 ..From terminal
106 .Remote indication over telephone line (e.g., telemetry)
107 ..Meter reading
108 .Telegraphy
109 ..Over telephone line
110 COMPOSITE SUBSTATION OR TERMINAL (E.G., HAVING CALCULATOR,
RADIO)
111 WITH USAGE MEASUREMENT (E.G., CALL OR TRAFFIC REGISTER)
112 .Computer or processor control
113 ..Call traffic recording
114 .Call charge metering or monitoring
115 ..Interexchange operations
116 ...Hardcopy record generating
117 ..Of station on polystation or party line
118 ...Identification of station
119 ..Hardcopy record generating (e.g., ticket printing)
120 ...With line identification or class of service determination
121 ..At central office
122 ...With display
123 ...Paystation (e.g., escrow control)
124 ...Pulse counting or accumulating (e.g., "message metering")
125 ....Local or zone
126 ....Automatic message accounting
127 .....Having line identification (e.g., automatic number
identification - "ANI")
128 ....Time of day controlled
129 ...Manually set (e.g., key and lock)
130 ..At subscriber station
131 ...Time controlled
132 ....Paystation (e.g., escrow control)
133 .Call traffic recording or monitoring
134 ..At central station
135 ...With hardcopy record generation (e.g., ticket printing)
136 ...With display
137 ...Trunk usage (e.g., peg count)
138 ....All trunks busy metering
139 ...Counting the number of completed connections
140 ..At subscriber
141 ...Mechanical register
142 WITH CALLING NUMBER DISPLAY OR RECORDING AT CALLED SUBSTATION
143 WITH CHECK OPERATED CONTROL (E.G., PAYSTATION)
144 .Other than coin
145 .Fraud or interference prevention
146 .Coin signalling or control
147 ..Coin box audit or totalizer
148 ..Denomination
149 ..Post-pay coin collection
150 ..Coin disposition (i.e., return or collection))
151 ...Upon connection to called station
152 ...Magnet, electromagnet, or relay controlled from central
office
153 ...Paystation (e.g., control by refund key)
154 .At central office
155 .At terminal station (e.g., coin paystation)
156 MULTI-LINE OR KEY SUBSTATION SYSTEM WITH SELECTIVE SWITCHING AND
CENTRAL SWITCHING OFFICE CONNECTION
157 .With special service
158 ..Conferencing
159 .With intercom system
160 ..With connection of intercom station to subscriber line
161 .With exclusion or priority feature (e.g., lockout or privacy)
162 .Detail of hold circuitry
163 ..Electronic
164 .Line status indication or call alerting
165 .Switching or supervision feature (e.g., common control,
digital)
166 .Detail of line circuit or line card
167 PRIVATE (E.G., HOUSE OR INTERCOM) OR SINGLE LINE SYSTEM
168 .Lockout
169 ..Central power source
170 .With paging
171 .Having plural stations with selective calling (e.g., master)
172 ..With call addressing
173 .With call addressing
174 .Including body or apparel supported terminal (e.g., headgear)
175 ..For underwater use (e.g., in diver's suit)
176 .With central power source
177 POLYSTATION LINE SYSTEM (I.E., PARTY LINE)
178 .Revertive call
179 .Call alerting (e.g., ringing)
180 ..Full selective or tuned (e.g., harmonic)
181 ..Semi-selective (e.g., line side, polarized)
182 .Automatic or unattended
183 ..Station identification
184 ..Lockout
185 .Portable or mobile
186 .Central power source
187 .Connected to central office
188 CALL OR TERMINAL ACCESS ALARM OR CONTROL
189 .Fraud or improper use mitigating or indication (e.g., "blue
box", "black box")
190 .Time out
191 ..At switching center
192 ...Of call duration (e.g., conversation timer)
193 ...Of specific equipment
194 .Lockout or double use signalling
195 ..In automatic system
196 .At switching center
197 ..Central office
198 ..PBX
199 .At substation
200 ..Restrictive dialing circuit
201 SPECIAL SERVICES
202 .Conferencing
203 ..Operator control
204 ..Subscriber controll
205 ...Conference initiation by single calling station
206 ..At substation
207 .At plural exchanges
208 .Priority override (e.g., butt-in)
209 .Repetitive call attempts (e.g., camp-on-busy, retry)
210 .Call diversion (e.g., call capture)
211 ..Call forwarding
212 ..Call transfer
213 ..Intercept (e.g., dead or changed number)
214 ..Secretarial or answering service
215 .Call waiting
216 .Abbreviated dialing or direct call (e.g., hot line)
217 .Audible paging
218 .Performed by operator (e.g., butt-in, busy verification)
219 PLURAL EXCHANGE NETWORK OR INTERCONNECTION
220 .With interexchange network routing
221 ..Alternate routing
222 .Toll center
223 ..With operator assistance
224 .Tandem switching center
225 .Multi-PBX interconnection
226 .Having a manual exchange
227 ..With an automatic exchange
228 ...Having signalling to operator
229 .Interexchange signalling
230 ..Signalling path distinct from trunk (e.g., CCIS)
231 ..Central office-to-PBX signalling
232 ...PBX trunk groups
233 ...Direct inward dialing
234 ..PBX to central office signalling (e.g., direct outward
dialing)
235 ..Voice frequency signalling over trunk
236 ..D.C. signalling over trunk
237 ...Pulse or digital signalling
238 ....Having signalling repeater
239 ....Using register-sender
240 ..Interexchange trunk circuit
241 ...Glare or simultaneous seizure mitigation
242 CENTRALIZED SWITCHING SYSTEM
243 .Class of service determination or transmission
244 ..In common control system
245 .Identification
246 ..Of line or trunk
247 ...With display
248 ...Using matrix
249 ...For nuisance call mitigation
250 .Four-wire switching
251 .With generating of call associated substation signal
252 ..For alerting signal at called station (e.g., ringing)
253 ...Electronic
254 ...Associated with connector
255 ...With interrupter
256 ..Having automatic or through ringing
257 ..For calling station (e.g., status or progress tones)
258 .Switching controlled in response to called station addressing
signal
259 ..Including deflected electron beam switching device or
mechanical or optical switching control (e.g., fluidic))
260 ..With operator position or completion of call (e.g., dial "O",
semiautomatic)
261 ...Operator controlled register-sender
262 ...Call extension by operator
263 ....With call indicator or annoucer
264 ....A to B operator
265 ...Call distribution to operator
266 ....Call queuing
267 ...Operator's console
268 ..Having shared or common switching control
269 ...Distributed control
270 ...In-stage or interstage scanning (e.g., link scanning)
271 ...Having multistage switching
272 ....Path selection or routing
273 .....Alternate routing
274 ......With busy or idle test
275 .....Including marking circuit
276 ......End-to-end marking (e.g., self-seeking)
277 .....With busy or idle test
278 ....Interstage junctor or "trunk"
279 ...Control reliability (e.g., redundancy)
280 ...Including registering or storing device for call address
signal
281 ....Conversion between dial pulse and voice frequency signal
282 ....Voice frequency receiver
283 .....Dual tone multifrequency (DTMF) receiver
284 ....With processor
285 ....With magnetic memory
286 ....Signal processing (e.g., dial pulse analysis)
287 ....Electronic
288 ....Register-sender
289 ...Translator
290 ...With time division of Control or supervisory signals
291 ...With detail of crosspoint switching structure (e.g.,
crossbar)
292 ....Electronic crosspoint (e.g., solid state)
293 ..Having line finder
294 ...Including electronic element (e.g., tube or semiconductor)
295 ...Plural
296 ..With repeater
297 ..Having specified busy-idle test
298 ..Direct control
299 ...Step-by-step system
300 ....Having plural wiper sets
301 ....Having potential control
302 ....Having rotary switch
303 ....Coordinate system (e.g., X-Y)
304 ...All relay type
305 ...Having motor-driven switch
306 ..With crosspoint switch detail
307 ..With power supply
308 .Switching apparatus for connecting calling line to operator's
position
309 ..Call distribution or queuing
310 .Divided central (e.g., communication between switchboards
311 ..Having signalling path feature
312 .Having multiple answering jacks for multipled line
313 .Multiple section switchboardd
314 ..Auxiliary (e.g., overflow)
315 .With line-signal control
316 ..Spring-jack cut-off
317 ..Relay cut-off
318 ..Central power source
319 .Single switchboard (e.g., cord circuit)
320 ..Switchboard circuit
321 ...Connection to operator's terminal
322 .Power supply
323 ..Power to switching equipment
324 ..Central power source (e.g., common battery, line current
feed)
325 .Structure of equipment
326 ..Wire or cable distribution
327 ...Main or intermediate distribution frame
328 ..Equipment mounting or support
329 ...Allowing movement of equipment (e.g., movable, modular)
330 ..Housing
331 .Having protective circuit
332 .Plug and socket
333 CONCENTRATOR OR TRUNK SELECTOR
334 .Concentrator-distributor pair (e.g., line concentrator)
335 .Using crossbar or crosspoint switching
336 .With magnet, electromagnet, or relay
337 .With busy-idle test (e.g., idle trunk finder)
338 REPEATER (E.G., VOICE FREQUENCY)
339 .With signal conversion (e.g., dial to DTMF, analog to PCM)
340 .Having line length compensation or equalization
341 .Pulse or tone repeater (e.g., electromechanical relay)
342 ..Electronic (e.g., logic circuitry)
343 .Controlled by a pilot or reference signal
344 .Component processes bidirectional signals
345 ..Including two-to-four wire conversion or hybrid circuit
346 .With frequency discriminator or negative impedance element
347 .With gain or attenuation control
348 .Transmission of power to distant repeater
349 .Having voice frequency transformer
350 SUPERVISORY OR CONTROL LINE SIGNALLING
351 .Signalling integrity protection (e.g., voice signal immunity)
352 .Substation originated
353 ..Conversion of signal form
354 ..With called number display
355 ..Repertory or abbreviated call signal generation
356 ...With dynamic memory
357 ...Insertable control element or circuitry (e.g., card)
358 ...By motor driven dial rotating device
359 ...Pulse signal generating (e.g., dialing)
360 ..Voice frequency band signalling (e.g., reed devices)
361 ...Electronic (e.g., tone generator)
362 ..Pulse signal generator (e.g., rotary dial)
363 ...Control of motor driven dial rotating device
364 ...With nonrotary actuator (e.g., key or slide type)
365 ...Specified switching contact (e.g., contact spring)
366 ...With detail of dial return mechanism (e.g., driving spring,
speed governor)
367 ...Finger wheel or mechanical adjunct (e.g., finger stop)
368 ..Plural-switch number input device (e.g., keypad)
369 ..Detail of mounting of switch pad or diall
370 ...In handset
371 ..Magneto signalling
372 .Signal reception at substation
373 ..Incoming call alerting (e.g., ringing)
374 ...With music or audible message generation
375 ...With electronic call sounder (e.g., tone "ringer")
376 ...With visual indication of incoming call
377 .Using line or loop condition detection (e.g., line circuit)
378 ..With current controlling electromagnetic core device (e.g.,
Hall-effect device)
379 ..With optical link between line and switching system
380 ..By bridge circuit
381 ..Busy test or make busy
382 ..For ring trip or polarity reversal detection
383 ..Of plural lines
384 ...By scanning
385 ..Relayless
386 .Signal receiver (e.g., tone decoder)
387 SUBSTATION OR TERMINAL CIRCUITRY
388 .For loudspeaking terminal
389 ..With circuitry for voice control of transmission direction
390 ..With amplification or attenuation level control
391 .Sidetone control or hybrid circuit (e.g., induction coil)
392 ..Suppression (e.g., antisidetone)
393 .Hold circuit
394 .Impedance matching or line equalizing
395 .Amplifying
396 .Visual signalling (e.g., lamp)
397 .Wire distribution
398 LINE EQUALIZATION OR IMPEDANCE MATCHING
399 SUBSCRIBER LINE OR TRANSMISSION LINE INTERFACE
400 .For line length compensation
401 ..Voltage boosting circuit
402 .Hybrid circuit
403 ..With adjustable balance circuit
404 ...Automatic adjustment
405 ..Electronic noninductive
406 .Echo suppression, antisinging, or reverse path blocking
407 ..Disable or inhibit
408 ..Control by pilot frequency signal
409 ..Having variolosser or attenuator
410 ..Echo cancellation (e.g., phase opposition)
411 ...Having transversal filter
412 .Protective circuit
413 .Power supply (e.g., battery feed)
414 TRANSMISSION LINE CONDITIONING
415 .Reactance neutralizing
416 .Interference suppression
417 ..Anti-crosstalk
418 CALL SIGNAL GENERATING (E.G., RINGING OR TONE GENERATOR)
419 TERMINAL
420 .Having loudspeaking conversation capability (e.g., hands-free
type or speakerphone)
421 .Having muting
422 .Switch or switch actuator structure
423 ..Line selection
424 ..Receiver or handset position responsive (e.g., hookswitch)
425 ...With mechanism for latching hookswitch or plunger againstt
motion
426 ...Movable holder for receiver or handset
427 ...Having plunger and lever linkage
428 .Housing or housing component
429 ..Having distinct circuitry support structure (e.g., circuit
board)
430 ..Body supported (e.g., headgear)
431 ..Separate housings for earphone and microphone (e.g.,
candlestick type)
432 ..Loudspeaking set
433 ..Handset structure
434 ..Specified terminal configuration (e.g., novelty type)
435 ..Wall set or convertible type
436 ..Desk set
437 ..Protective structure
438 ...Of cord or connector
439 ...Antiseptic
440 ..Casing or enclosure, per se.
441 TERMINAL ACCESSORY OR AUXILIARY EQUIPMENT
442 .With circuit connection to terminal
443 .Including coupler (e.g., inductive)
444 ..Acoustic
445 .Locking device
446 .Telephone receiver support
447 .Attachable to terminal housing
448 ..Hookswitch operator
449 ..Handset holder (e.g., shoulder rest)
450 ..Clips onto terminal structure
451 .Protective structure
452 ..Antiseptic, disinfecting or disposable
453 .Hood or enclosure (e.g., booth)
454 .Support or stand
455 ..Handset holder
456 .Dialing tool
457 MISCELLANEOUS