Analogue Raytheon radar problems

[Sgeir]

Towards the end of last season the radar image on our Raytheon C80 plotter went to pot, as in the attached pics.

We've since had the C80 checked over by The Service Centre and, although there had been an (apparently) unrelated minor fault, it now seems OK after repair. The radar image remains the same, ie the scanner appears to be turning but the signal is unreadable on the C80 screen

I have checked the through-hull cabling; there has been no water ingress in that area and the joint between the cable from the radome and the cable to the MFD is bone dry in an area above the salooon headlining. The cable feels dry to the touch and the conductors show no sign of discolouration.

Any ideas? Water in the radome perhaps, or just old and knackered?

 

[srm]

Have you tried adjusting the gain and clutter controls and looked at different ranges?
Try 3 mile range, turn sea clutter off and adjust gain so that it is just on the threshold where background noise shows as a light speckle. The set should then show any targets within range.
If the interference pattern persists the fault could be in the scanner but may be the radar signal processor in the display unit.
Open up the dome and check that the cable connections are all clean, dry and secure.

If that does not resolve the problem you need a technician who knows the equipment.

 

[yotter]

Just back from the boat, I have just run a new (to me) mast cable. Happily my aging C80 analogue radar is now working.

Have you tried running the self test and diagnostics. There may be an error message in there somewhere.

 

[dslittle]

Just back from the boat

That will have been a bit of a trip…

 

[yotter]

Took me ages to do the passage plan

 

[Sgeir]

Thanks for the comments, folks. As well as having the C80 MFD checked over, I've done all the usual checks plus manual tuning/gain etc, but nothing untoward has shown up. However I have not yet opened the radome to check connections etc.

Once again, thanks for all the comments.

 

[Skylark]

@Seir The only thing I’ve seen remotely similar to your pictures is a TV screen with a dodgy lead from the DVD player. The limit of my knowledge of electrickery is 1. Turn off and on again, and 2. Remove cables and plugs and apply Switch Cleaner. Quite remarkable just how helpful these two actions can be. Good luck.