Here is a rough idea for new categorization. These are not intended to be complete lists of subcategories, and names can be improved. I found "telecommunications engineering" and "data communications" problematic under this categorization. I copied existing category names (these categories are easily moved) and made up some new names too. Most of the leaf nodes are brainstormed examples and may need subcategories.

Communication

  1. Mass media
    1. Videos and DVDs
    2. Film and video technology
    3. Television
    4. Digital media
  2. Telecommunications
    1. Broadcasting (this has mostly nontech articles currently, so I moved this here)
    2. Telecommunication conferences (?)
    3. Telecommunication services
    4. Telecommunications economics
    5. Telecommunications history
    6. Telecommunications law
    7. Telecommunications organizations
    8. Telecommunications stubs
    9. Telecommunications companies
    10. Telecommunications by country
    11. Privacy of telecommunications (this has mostly nontech articles currently, so I moved this here)
    12. Military communications (this has mostly nontech articles currently, so I moved this here)
    13. Computer and telecommunication standards (?)
    14. Applications of Telecommunications (->new, maybe fits under tech too, depending on the contents?)
      1. Radiometry
      2. Telecommuting (not telecom)
      3. Teleconferencing
      4. Telegrams
      5. Amateur radio
      6. Satellite radio
      7. Radar
      8. Radio navigation
      9. RFID
    15. Telecommunications equipment (?)
    16. Telecommunications technology (the new general wide category for the real tech stuff)
      1. Telecommunications terms (?)
      2. Analog modulation
        1. FM
        2. AM
      3. Digital modulation (maybe only one modulation category?)
        1. PSK
        2. QAM
        3. OFDM
        4. Spread spectrum
        5. Synchronization
        6. Equalization
      4. Line codes
        1. NRZ
        2. Manchester
      5. Channel access methods
        1. CDMA
        2. Time-slotted
        3. Multiplexed (?)
      6. Error detection and correction
        1. CRC
        2. Reed-Solomon
      7. Telecommunication by media types
        1. Fiber optics
          1. Multimode
          2. Singlemode
        2. Wireless technology
        3. Wired communications
          1. Twisted pair
          2. Coax
        4. Exotic (acoustic maybe?)
      8. Telecommunication channel related topics
        1. WDM
        2. Chromatic dispersion
        3. Noise
        4. Multipath
        5. Distortions
        6. Radio spectrum
        7. Radio propagation
      9. Ways to implement telecommunication (name? telecom building blocks?)
        1. Analog RF blocks
          1. Mixers
          2. Modulation
          3. PLLs
        2. Antennas
        3. Digital electronics
        4. Filter theory
        5. Signal processing
      10. Telecommunications system planning
        1. Radio resource management
        2. Network management
        3. Spectral efficiency
        4. RF power budget
      11. Data transmission (???)
      12. Telecommunication theory (mathematical or theoretical topics here)
        1. Information theory
        2. Complex signals
        3. Fourier analysis/signals
        4. Stochastic processes
      13. Packet switching
        1. Packet scheduling
        2. Queuing
        3. GCRA
        4. Weighted fair queuing
        5. QoS
        6. Routing
      14. Computer networking
      15. Telecommunications systems
        1. Telephony (POTS)
          1. Speech codecs
          2. On-hook
        2. ATM
        3. SDH/Sonet
        4. Spelling alphabet
        5. Mobile telephony
        6. Amateur radio
        7. Television
        8. Radio
        9. GPS (?)
        10. Bluetooth
        11. Packet radio
        12. Wi-Fi
        13. Walkie-talkie