RJ45 and RJ11 Network LAN Cable Tester 9V Battery with LED Indicators RJ12 CAT5 CAT6 UTP Ethernet

Key Features and Description:

• Dual Compatibility (RJ45 & RJ11):
  • RJ45: Primarily used for Ethernet network cables (Cat5, Cat5e, Cat6, etc.). It tests 8-conductor network cables.
  • RJ11: Used for standard telephone cables, typically 2- or 4-conductor.
  • This dual functionality makes it a versatile tool for various cabling needs.
• Two-Unit Design (Master and Remote):
  • The tester consists of two detachable units: a master unit and a remote unit.
  • This design is crucial for testing cables that are already installed, such as those running through walls or between patch panels and wall jacks. One unit plugs into one end of the cable, and the other unit plugs into the distant end.
• LED Indicators:
  • Both the master and remote units typically feature a series of 8 or 9 LED lights (one for each wire pair and sometimes a ground indicator).
  • These LEDs light up in a sequential pattern, indicating the continuity and correct pinout of each individual wire within the cable.
  • By observing the sequence and which LEDs illuminate (or don’t), you can quickly identify:
    • Open circuits: An LED on one unit lights up, but the corresponding LED on the other unit does not, indicating a broken wire.
    • Short circuits: Multiple LEDs light up simultaneously when they shouldn’t, indicating wires are touching.
    • Miswires/Crossover: The sequence of lights is different between the master and remote units, indicating that the wires are terminated in a non-standard or incorrect order (e.g., a straight-through cable showing as a crossover, or vice-versa, or just a general misconfiguration).
    • No connection: No LEDs light up, indicating a complete break in the cable or a very poor connection.
• Test Modes (Often):
  • Many testers have an “ON” mode for a continuous, fast scan and a “SLOW” mode for a slower, more deliberate scan of the wire sequence, which can be helpful for detailed analysis. Some may also have an “OFF” mode to conserve battery.
• Portability and Power:
  • These testers are typically compact, lightweight, and handheld, making them easy to carry for on-site work.
  • They are usually battery-operated, most commonly using a 9V battery (not  included).
  • Model Number (AD-LT-389):
    • “AD-LT-389” is likely a specific model or part number from a manufacturer. This number helps identify the exact product from a particular brand, “AD” means brand, “LT” for LAN Tester, and “389” a unique identifier

Typical Applications:

• Troubleshooting: Quickly diagnosing connectivity issues in existing network or phone lines.
• Installation: Verifying newly terminated cables or installed wiring to ensure they meet standards before deployment.
• Cable Manufacturing/Assembly: For those who make their own custom patch cables, it’s indispensable for confirming correct wiring.