Testing and troubleshooting analog radar cables for Raymarine – Complete guide

In situations where radar cables are frequently connected and disconnected from the radome, radar pedestal, display, junction boxes, or terminal strips, the cable can be damaged. Here we go through cable resistance tests used to diagnose analog video radar cables for hsb/hsb2/SL Pathfinder Series Radar Displays, C-Series Classic MFDs, and E-Series Classic MFDs.

Step-by-step: Analog radar scanner communication check

1. Disconnect the radar cable: Unplug the cable from the display's radar connector and turn off power to the radar scanner (applies to open arrays). Measure the resistance between pin 6 and pin 10 – the value should be 160 Ohm. If correct, proceed to step 5.
2. Check wiring: Open the radar scanner's cover and inspect pin 3 (blue) and pin 4 (green). Repair if necessary.
3. Measure on the processor board: Disconnect the connector from the scanner's processor board and measure the resistance between pin 3 and pin 4. If the value is 160 Ohm, the cable is defective and should be replaced.
4. Radome fault: If the resistance is not correct, the radome is faulty. Since analog radomes are no longer serviced by Raymarine, replacement must be sought on the second-hand market or an upgrade to modern radar considered.
5. Check the display: If the cable and scanner are OK, measure the resistance between pin 6 and 10 in the display's connector. If the value is not 160 Ohm, the display's radar processor circuits are defective. Here too, replacement via the second-hand market or an upgrade is required.

Important tips and tolerances

For video, analog, and trigger wires, there are no exact tolerances. The test aims to detect open circuits. A fault may require replacement of the radome connector, radar pedestal connector, cable, radome, or radar display.

Replacement cables for analog radar

Below are examples of replacement cables for analog video radomes:

Below are examples of cables for analog video pedestals:

Availability and part numbers

Part number for Radome Connector: R126. Part number for Open Array Pedestal Connector: R58056. Unfortunately, these parts are no longer available. All new Raymarine radomes and radar pedestals use Ethernet communication, which means that the production of analog cables has ceased. Availability is therefore limited to the second-hand market.