PTO Manual of Classification for US patents

PTO Manual of Classification for US patents

What follows are the subclasses from one class of the Manual of Classification for US patents. As you scroll through the list and encounter a class/subclass of interest, you can jump back to the top and retrieve patent titles by entering the class/subclass in the box below.


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363-131 121-55A 14-.5
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Class Number: 455
 Class Title: TELECOMMUNICATIONS

Subclass  Subclass
Number    Title

  1       INTERFERENCE SIGNAL TRANSMISSION (E.G., JAMMING)
  2       AUDIENCE SURVEY AND USE ACCOUNTING
  3.1     DISTRIBUTION SYSTEM (E.G., PLURAL CABLES, ETC.)
  3.2     .Receiver for satellite broadcast
  3.3     .Combined with power distribution network
  4.1     .Remote control of distribution
  4.2     ..With subscriber selection or switching
  5.1     .Two-way
  6.1     .Common antenna or cable
  6.2     ..With specific cable converter
  6.3     .Combined with diverse type art device (e.g., audio/sound
            or entertainment systems, etc.)
  7       CARRIER WAVE REPEATER OR RELAY SYSTEM (I.E., RETRANSMISSION OF
           SAME INFORMATION)
  8       .Failure compensation (e.g., spare channel)
  9       .Monitoring
  10      ..Fading compensation
  11.1    .Portable or mobile repeater
  12.1    ..Space satellite
  13.1    ...With plural repeater or relay systems
  13.2    ...With synchronizing of satellites or system
  13.3    ...With antenna feed network or multiple antenna switching
  13.4    ...Power control
  14      .With transmission line
  15      .Two separate way transmission
  16      ..Simultaneous using plural repeaters at each location
  17      .Plural modulated carriers
  18      .With delay or recording
  19      .Common antenna
  20      .With frequency conversion
  21      ..With demodulator
  22      ..Plural conversion stages
  23      .Frequency or phase modulation
  24      .Transmitter/receiver feedback compensation
  25      .Directive antenna
  26.1    USE OR ACCESS BLOCKING (E.G., LOCKING SWITCH)
  31.1    SYSTEM WITH RECEIVER SELECTION
  32.1    .Receiver scans for address signal
  33.1    .Zoned or cellular
  33.2    ..Hand-off control
  33.3    ...Using plural antennas
  33.4    ..With overlapping zones
  34.1    .Exclusive assigned channel
  34.2    .Seized channel
  35.1    .Tone coded squelch
  36.1    ..Plural tones
  37.1    ...Difference frequency
  38.1    .Coded sequence
  38.2    ..With actuation (e.g., turn on/off or alarm indication,
             etc.)
  38.3    ...Power control or battery saving
  38.4    ...Visual indicationn
  38.5    ...Tone sequence
  39      TRANSMITTER AND RECEIVER AT SEPARATE STATIONS
  40      .Earth or water medium
  41      .Near field (e.g., inductive or capacitive coupling)
  42      .Frequency or phase modulation
  43      ..With modification of frequencies of analog signal passed
             (e.g., pre-emphasis and de-emphasis)
  44      ..With stated modulation index
  45      ..Via subcarrier
  46      .Suppressed carrier wave system
  47      .Single or vestigial sideband system
  48      .Inverted sideband
  49.1    .Plural transmitters or receivers (i.e., more than two
            stations)
  50.1    ..Noise, distortion, or singing reduction
  51.1    ...Synchronized stations
  51.2    ....Simulcast system
  52.1    ...Fading compensation
  52.2    ....Due to weather attenuation
  52.3    ....Rayleigh or multipath fading
  53.1    ..With central station (e.g., master, etc.)
  54.1    ...To or from mobile station
  54.2    ....With service request and response
  55.1    ....Using radiating transmission line
  56.1    ....Multiple base stations
  57.1    ...Plural receivers tuned to common frequency
  58.1    ..Break-in or priority override
  58.2    ..Lockout or busy-idle signalling
  59      .Single message via plural carrier wave transmission
  60      ..Different phases of same frequency carrier
  61      .Single message via plural modulation of single carrier
  62      .Optimum frequency selection
  63      .Distortion, noise, or other interference prevention, reduction,
            or compensation
  64      ..Plasma source or barrier
  65      ..Anti-multipath
  66      .With diverse art device
  67.1    .With measuring, testing, or monitoring of system or part
  67.2    ..Using a chamber (e.g., room testing or audio
             surveillance, etc.)
  67.3    ..Noise, distortion or unwanted signal detection (e.g.,
             quality control, etc.)
  67.4    ..Using a test signal
  67.5    ..Of a microwave link or system
  67.6    ..Phase measuring (e.g., group delay, propagation effects,
             etc.)
  67.7    ..With indication (e.g., visual or voice signalling, etc.)
  68      .With control signal
  69      ..Transmitter controlled by signal feedback from receiver
  70      ..Receiver control signal originates at message transmitter
  71      ...Frequency control
  72      ...For compression and expansion of message signal (i.e.,
              companding)
  73      TRANSMITTER AND RECEIVER AT SAME STATION (E.G., TRANSCEIVER)
  74      .Convertible (e.g., to diverse art device)
  75      .With frequency stabilization (e.g., automatic frequency
            control)
  76      ..Synthesizerr
  77      .With tuning
  78      .With transmitter-receiver switching or interaction prevention
  79      ..Automatic (e.g., voice operated)
  80      ...With distributed parameter coupling
  81      ....Waveguide
  82      ...Common antenna
  83      ..Single antenna switched between transmitter and receiver
  84      .With a common signal processing stage
  85      ..Transmitter oscillator used as detector
  86      ..Transmitter oscillator used as local oscillator
  87      ...Tunable or variable
  88      .Transceiver controlling a separate transceiver or receiver
  89      .Portable or mobile
  90      .Housing or support
  91      TRANSMITTER
  92      .Remote control of a transmitter
  93      .Convertible to different type (e.g., AM to FM)
  94      .Alternator
  95      .Mobile or portable
  96      ..Transmitter ejected from moving vehicle
  97      ..With antenna ejection or external support
  98      ..With aircraft, satellite, or projectile
  99      ..With vehicle
  100     ..Body attached or connected
  101     .Diversity
  102     .Plural modulation
  103     .Plural separate transmitters or channels
  104     ..Carrier and sidebands separately transmitted
  105     ..Common frequency
  106     .Modulation by absorption, shielding, or reflecting
  107     .With variation of antenna impedance or dimension for
            modulation
  108     .Amplitude modulation
  109     ..Vestigial or single sideband or suppressed carrier
  110     .Angle modulation
  111     ..Including distributed parameter structure
  112     ..With frequency multiplication or division
  113     ..With frequency control
  114     .With harmonic radiation suppression
  115     .Measuring, testing, or monitoring of transmitter
  116     .Carrier amplitude control (e.g., voice operated on/off)
  117     .With electrical protection of transmitter circuit or operator
  118     .Frequency conversion
  119     .Carrier frequency stabilization
  120     .Including tuning
  121     ..In antenna circuit
  122     ...With saturable reactor
  123     ...Automatically controlled
  124     ..Distributed parameter device
  125     ..Automatic adjustment of tuning
  126     .With feedback of modulated output signal
  127     .Power or bias voltage supply
  128     .With casing or housing
  129     .With coupled antenna
  130     RECEIVER OR ANALOG MODULATED SIGNAL FREQUENCY CONVERTER
  131     .Frequency conversion between signal source (e.g., wave
            collector) and receiver
  132     .Plural receiverss
  133     ..With output selecting
  134     ...By signal strength
  135     ...By signal quality (e.g., signal to noise ratio)
  136     ...With control (e.g., automatic gain control, automatic
              frequency control, etc.)
  137     ..With output combining
  138     ...With control (e.g., automatic gain control)
  139     ....Frequency or phase control
  140     ..Selectively actuated or controlled
  141     ..Including common stage (e.g., local oscillator)
  142     .Convertible to different type (e.g., AM to FM)
  143     ..With distinct signal path for each type
  144     ..With dual purpose amplifying or other stage
  145     .Panoramic display
  146     ..Plural separate paths or plural oscillators
  147     ..Particular local oscillator control
  148     ..With oscilloscope sweep signal derivation or control
  149     .Plural output (e.g., plural speakers ) (not stereo)
  150.1   .Signal selection based on frequency (e.g., tuning)
  151.1   ..Remote control of channel or station selection
  151.2   ...Wireless link (sonic, RF or infrared)
  151.3   ...Remote oscillator tuned
  151.4   ...Plural electronic devices controlled
  152.1   ...Of or combined with vehicle receiver
  153.1   ...Mechanical
  153.2   ....With wired link
  154.1   ..With indication of frequency, channel, or selector
             condition (e.g., tuning aid)
  154.2   ...Scanning display
  155.1   ...By meter
  156.1   ...Audible indicator
  157.1   ...Analog frequency indication (e.g., dial)
  157.2   ....With light indication or bar type
  158.1   ...Channel index indication
  158.2   ....With electronic digital indication
  158.3   .....Using a counter
  158.4   ....With multiple display functions
  158.5   ....Non-numeric display (e.g., call letters)
  159.1   ...Variable light indication
  159.2   ....Plural lamps
  160.1   ..Plural tuning modes (e.g., manual and scanning, etc.)
  161.1   ..Frequency scanning
  161.2   ...With processor control
  161.3   ...Using signal strength or quality
  162.1   ...Motor activated
  163.1   ....Reversible motor (e.g., end-stop control)
  164.1   ...With automatic frequency control
  164.2   ....Processor controlled (AFC)
  165.1   ...With frequency synthesizer
  166.1   ...With channel skipping selection
  166.2   ....With priority channel selection
  167.1   ...With dual sweeping
  168.1   ...Multiband
  169.1   ...With particular variable voltage or current tuning
  169.2   ....With varactor diode
  170.1   ..With mechanical or electromechanical selection
  171.1   ...Time actuated
  172.1   ....Including a motorr
  173.1   ...With automatic frequency control of fine tuning
  174.1   ...With muting (e.g., silent tuning)
  175.1   ...With carrier wave preset
  176.1   ...Combined with band selection
  177.1   ...Combined with other control (e.g., bandwidth, volume,
              gain, etc.)
  178.1   ...With plurality of tunable circuits
  179.1   ..Channel or station selection
  180.1   ...Combined with band selection
  180.2   ....UHF and VHF
  180.3   .....With phase locked loop (PLL) tuning
  180.4   .....Varactor tuned (e.g., varactor diode)
  181.1   ...Time controlled
  182.1   ...With frequency control
  182.2   ....Automatic (AFC)
  182.3   ...Fine tuning
  183.1   ...With frequency synthesizer
  183.2   ....Processor controlled
  184.1   ...With comparing desired and existing tuning conditions
  185.1   ...With channel information storage
  186.1   ....With memory control or programming
  186.2   .....Having a keyboard
  187.1   ...Separate tuned circuits for each channel or station
  188.1   ..Band selection
  188.2   ...UHF and VHF
  189.1   ...With plural separate mixer or converter circuits
  190.1   ...With frequency conversion
  191.1   ...With plurality of tuned circuits
  191.2   ....Varactor tuned
  191.3   ....With switching between stages
  192.1   ..With frequency control
  192.2   ...Automatic (AFC)
  192.3   ...Fine tuning
  193.1   ..With antenna circuit tuning
  193.2   ...With plural resonant circuits
  193.3   ...Including varactor diode
  194.1   ..With muting (e.g., silent tuning)
  194.2   ...Amplifier controlled
  195.1   ..Variable voltage or current tuning
  196.1   ..Including variation of local oscillator frequency
  197.1   ...By simultaneous control with signal selection
  197.2   ....Variable capacitor tuned
  197.3   .....Including additional tuning circuit
  198.1   ....Including distributed parameter control device
  199.1   ....Discrete frequency types (e.g., channel switching)
  200.1   ..With other control (e.g., volume, gain, bandwidth, etc.)
  201     .Exalted carrier
  202     .Suppressed carrier
  203     .Carrier and single sideband
  204     .Vestigial sideband
  205     .Frequency or phase modulation
  206     ..Responsive to one of overlapping signals
  207     ..With plural conversion
  208     ..With synchronized or controlled local oscillator
  209     ...Plural local oscillators or mixers
  210     ..With carrier amplitude modulation elimination (e.g., specified
             limiter)
  211     ...Combined with other functionn
  212     ..With squelch or other audio output silencing
  213     ...Using specified filter
  214     ..With particular discriminator or detector
  215     ...Superregenerative
  216     ..With particular frequency division or multiplication
  217     .With protection circuit for receiver circuit
  218     .Squelch
  219     ..With automatic gain or volume control
  220     ..Adjustable
  221     ..Audio responsive
  222     ..Noise controlled
  223     ...Short duration (noise blankers)
  224     ....Separate broadband detector channel
  225     ..Plural paths
  226.1   .Measuring or testing of receiver
  226.2   ..Signal strength
  226.3   ..Signal-to-noise ratio
  226.4   ..With meter or indicator
  227     .Responsive to an input signal of particular predetermined
            frequency
  228     ..Responsive to specified modulation (e.g., call alarm,
             Conelrad)
  229     ..Responsive to carrier absence or presence
  230     .Local control of receiver operation
  231     ..Applied at or for specific intervals or periods of time
  232.1   ..Gain control
  233.1   ...With diverse control (tone, etc.)
  234.1   ...Automatic
  234.2   ....Processor controlled
  235.1   ....Forward acting
  236.1   ....Variable conversion efficiency (variable oscillator
               amplitude, etc.)
  237.1   ....Responsive to locally injected pilot
  238.1   ....Responsive to vehicle speed
  239.1   ....Nonlinear automatic gain control
  240.1   .....Variable automatic gain control loop gain
  241.1   .....Different gain stages
  242.1   .....Delayed
  242.2   ......Different delay for different signal stages or
                 thresholds
  243.1   ......Radio frequency stage only delayed
  244.1   .....Dual time constant
  245.1   ....Automatic gain control signal derived from information
               signal
  245.2   .....Plural stages controlled
  246.1   ....Responsive to plural inputs
  247.1   .....Separate automatic gain control signals
  248.1   ....Constant or controlled input impedance
  249.1   ....Variable attenuator type
  250.1   ....Automatic gain control to improve strong signal
               handling
  251.1   ....Plural stages with different levels or bias to each
               stage (e.g., partial automatic gain control)
  252.1   ....Semicondutor
  253.1   ....Plural stages controlled with plates, screen grids, or
               cathodes connected in parallel
  253.2   ....Plural amplifier stages
  254     ..Sensitivity controll
  255     ..Local oscillator frequency control
  256     ...Combined with other control
  257     ...Automatic
  258     ....Utilizing particular local oscillator control
  259     .....Reference oscillator or source
  260     ......Phase lock loop or frequency synthesizer
  261     .....Variable reactance (e.g., reactance tube)
  262     ......Voltage controlled capacitor
  263     .....Discriminator or detector
  264     .....Voltage control of oscillator
  265     ....With local oscillator synchronization or locking
  266     ..Selectivity or bandwidth control
  267     ..Tone control
  268     ..Fidelity control
  269     .With wave collector (e.g., antenna)
  270     ..Power-line or receiver element used as wave collector
  271     ..Suppression of radiation from receiver via wave collector
  272     ..Plural separate collectors
  273     ...With paticular output combining
  274     ....Loop or coil antenna
  275     ...With frequency changing or selecting in the output path of
              one or more collectors
  276.1   ...With phase shifting, correcting, or regulating in the
              output path of one or more collectors
  277.1   ...Selectively or alternately connected to receiver
  277.2   ....By signal quality (e.g., noise)
  278.1   ...Combined with noise or interference elimination
  279.1   ....Plural antenna currents entering single transformer
  280     ..With coupling to a stage of the receiver
  281     ...Having distributed parameters
  282     ....Transmission line
  283     ...Undesired signal or noise control (e.g., antistatic)
  284     ....Balancing or cancelling
  285     ....With image frequency suppression
  286     ....Wave filter, coil, or wave trap
  287     ....Shunt or bypass
  288     ....Particular composition (e.g., of cell or element)
  289     ...With coupling varying, regulating, or control
  290     ...Including passive tuned circuit
  291     ...Using active device (e.g., as preamplifier or reactance)
  292     ...Transformer or other passive inductance
  293     ...Specified stage (e.g., mixer, amplifier, or demodulator)
  294     ....With particular electron tube structure
  295     .Modulation distortion or cross talk correction or elimination
  296     .Noise or interference elimination
  297     ..In vehicle
  298     ..Originating in power supply
  299     ...Filter or rectification in power supply energized by
              fluctuating or a.c. source
  300     ..By shielding
  301     ...Plural or compartmented shielding structure
  302     ..Image frequency suppression
  303     ..Using plural separate signal paths
  304     ...Phase shift in at least one path
  305     ...With balancing or neutralizing
  306     ....Filter in at least one path
  307     ..With specific filter structure
  308     ..With amplitude limiterr
  309     ...In demodulator or low frequency (audio amplifier circuit)
  310     ..Internally generated noise or oscillations
  311     ..In radio frequency amplifier, intermediate frequency amplifier
             or converter circuit
  312     ..In demodulator or low frequency (e.g., audio frequency)
  313     .Frequency modifying or conversion
  314     ..Plural separate successive conversions
  315     ...With plural separate local oscillators
  316     ....With frequency stabilization for at least one local
               oscillator
  317     ..Unwanted oscillation or radiation prevention
  318     ..With specified local oscillator structure or coupling
  319     ...With particular coupling
  320     ....Lumped impedance
  321     ...In a single envelope or with common active element (e.g.,
              autodyne)
  322     ....Plural common electrode
  323     ..Particular frequency conversion structure or circuitry
  324     ...Homodyne (i.e., zero beat or synchrodyne reception)
  325     ...Including distributed electrical parameter structure
  326     ....With balanced mixer
  327     .....Stripline
  328     .....Hollow waveguide
  329     ....Electron beam tube
  330     ....With nonlinear impedance (e.g., diode)
  331     ...Crystal or electron tube diode
  332     ...Push-pull
  333     ...Transistor or integrated circuit
  334     .With particular receiver circuit
  335     ..Plural diverse function tube or stage (performs plural
             functions alternately or concurrently)
  336     ..Superregenerative detector or discriminator
  337     ..Discriminator or demodulator
  338     ..Coupling or decoupling between stages
  339     ...Band pass filter
  340     ...Variably tunable or adjustable
  341     ..Amplifier
  342     ...Reflex type
  343     ..With particular power or bias supply (includes battery saving
             means and includes self-powered)
  344     .Combined with diverse art device
  345     ..With vehicle
  346     ...Detachable for portability
  347     .Cabinet, housing, or chassis structure
  348     ..With retractable or readily detachable chassis
  349     ..Sectional or interconnectable (e.g., modules)
  350     ..With particular speaker mounting
  351     ..Transportable
  352     .Remote control of receiver
  353     ..Plural conditions from remote station
  354     ...Mechanical
  355     ..Amplitude, volume, or gain control
  899     MISCELLANEOUS