United Data Corporation

A Proctor Company


Long Loop Adapters


Telephone Demonstrators

Privacy Modules

Telephone Power Supply





Single Line Privacy

41403 Line Guard
Model 41403 Line Guard

The Proctor Model 41403 Line Guard privacy devices can be used in the home or office to give modem, FAX and other types of data transmission devices uninterrupted use of the phone line as soon as they access it. The modules can also be used to protect private telephones from eavesdropping and annoying interruptions and to assure the integrity of private telephone conversations.

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How It Works

41403 Schematic

The 41403 is a balanced exclusion module that installs in series anywhere in the tip and ring path, or inside the telephone or wall jack to be restricted. Any data device or telephone equipped with a Line Guard will be restricted from accessing a call already in progress; devices or phones not equipped with a privacy module will always have access to the line. The modules allow add-on conferencing between Line Guard equipped and/or non-equipped telephones with a simple hookswitch operation.

Typical Single-Line Application

41403 Application

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Key Benefits

    A balanced disconnection (both tip and ring)
    provides maximum voice and data privacy
    Works with all standard (48Vdc idle line)
    telephone systems.
    Can be used on any number of data and
    phone extensions without adversely affecting
    their transmission, signaling, and pulsing
    The modules do not require any external
    power source.
    FCC registered.

Model 41403 Specifications

    • Spade Lugs
    • Operating Voltage: 48VDC
    • Loop Limits: Up to 1.5k Ohms
    • Attenuation - Unoperated: <0.2dB @ 2kHz
    • Attenuation - Operated: -75dB
    • Operating Temperature:  0 to 50C
    • 0% to 95% Non-Condensing
    • Dimen: 1.0" (25mm) W x 0.75" (19mm) H
      x 0.25" (6mm)D
    • Wt: 1.0 oz (28 grams) 



Copyright United Data Corporation, Inc.


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