[TG] No Radar Source Found

[flying fish]

Flying Fish Requesting Raymarine Radar Troubleshooting Help--I am getting ready to sail into the busy Torres Straits and my radar is inop. The chart plotter message is "No Radar Source Found." I've gone aloft to check out the connections on the dome and they are good. I have power going from my panel switch to the electronics. The system boots up okay. AIS functions on the radar screen. But there is no radar signature and the Transmit/Standby button is grayed out. I have the Raymarine 4kW 24" HD Color Radome, installed about 30 months ago. There are no Raymarine Service Centers in this part of Australia. Any suggestions would be greatly welcomed. Thank you.

[Tom - Raymarine - Moderator]

Hello Flying Fish,

Where specifically are you, and are you based there or travelling? If so, what's your next port of call? We have good service dealers in Cairns and Darwin but you're correct, not in between.

Apart from an actual hardware fault - which is very hard to diagnose conclusively without spares or test tools - it's not at all unusual to get problems like this from a non-obvious problem somewhere in the cabling between the radar and display.
We quite commonly come across systems where you have a reasonable battery and distribution-panel voltage but a significant drop along the run of the cabling to the radar, when under load, so that the supply reaching the scanner is insufficient (a measurement when there's no load on the supply, with cable disconnected from the scanner, will probably look ok) due to a high-resistance (loose, corroded etc.) connection somewhere in the line.
Similarly, the network connection itself can - and is far more likely to - suffer a poor contact or high-impedance connection somewhere in-line which might look sound to a visual inspection but which won't pass high-bandwidth ethernet traffic.
If you have suitable cables aboard you may be able to eliminate these by bypassing the installed power and network cabling and connecting straight to the scanner circuit boards instead. If you are able to run some suitable cable loosely up to the scanner you can probably temporarily connect into the 2-pin power header and run straight back to a (fused) supply off the battery in order to bypass the power cable run, and you can run a Cat5 ethernet cable to the RJ45 network socket on the IF board in the scanner to bypass the ethernet network cabling. You'd need to be able to connect the other end of the Cat5 cabling into your MFD's network, via a Raynet-RJ45 adaptor cable or a SeatalkHS network switch (most of our current products use a proprietary Raynet connector, but you've not said what the other products on your boat.)

Failing either of these, I think you need to get the radar and display checked as a system by either of the nearest dealers, ideally.

Regards,
Tom