Sync Signal Jrc Radar - No
Generated by the TXRX board to tell the display unit exactly when the magnetron fires.
To fix the problem, you must first understand the signal chain. In any analog or hybrid radar system, the scanner (antenna unit) and the display processor must remain in perfect synchronization.
Over time, vibrations can cause cracks on the display PCB, leading to sporadic "no signal" issues. 4. Troubleshooting by JRC Model
The inter-switching cable can break or suffer from saltwater corrosion inside the outer insulation. Inspect the cable for physical damage, particularly near the scanner entry.
Ensure the radar scanner is switched off and isolated before getting close to the array. no sync signal jrc radar
Do not trust the cable first. Test thermally – heat gun/cold spray localizes the fault.
Check the rubber O-ring seal on the scanner housing door every season. Dry rot allows water inside, which shorts out the transceiver electronics.
If the connectors are clean and tight, and the scanner is rotating, the problem is likely an internal component failure (encoder, TXRX, or motherboard). These require professional repair.
The "Sync" or "AZI" (Azimuth) signals travel through the multi-core installation cable. Corrosion or loose pins at the junction box or the scanner unit's terminal board often cause signal loss. Generated by the TXRX board to tell the
Receives commands, rotates, transmits pulses, and sends back data (video, azimuth, sync).
: Simultaneously, a low-voltage "Sync" or "Trigger" pulse is sent down the main equipment cable to the display unit.
In rarer cases, the processor board within the main display unit may fail to process the sync signal, even if the scanner is sending it. 3. Likely Causes of "No Sync Signal" Potential Fault Inter-Switching Cable
The sync circuit is closely linked with the rotation assembly. Over time, vibrations can cause cracks on the
If you've confirmed the basic checks are fine, the problem is likely with a specific component. Understanding the function of each can help you pinpoint the issue.
The error on a JRC radar is intimidating, but it is a logical, traceable fault. In 9 out of 10 cases, it is a cabling issue (corrosion or broken conductor) or a failing azimuth sensor. However, the remaining cases require oscilloscope analysis and knowledge of JRC’s unique interface board architecture.
In one documented field service case, a JMR-9230-S radar on a vessel in Tianjin, China, exhibited a blinking screen that shut down after startup. The crew had placed external cooling fans to combat overheating, but the problem persisted. Service technicians traced the issue to the CCU (Central Control Unit) rather than any sync circuit directly. The CCU, a NDC-1590A module, was replaced entirely after confirming that cable connections, display, and SSD were functional. This case illustrates how radar failures can mimic one another—what appears initially as a sync signal fault may ultimately be a control unit problem.
To diagnose the failure, you must understand what the sync signal does. A marine radar depends on tight microsecond-level timing to calculate target data:
