old radar not functioning - solution too simple?

[Banooma]

I bought my boat with a Raymarine radome and Autohelm radar display, plus wind, speed, and depth meters on my navpod. At some point the previous owner swapped out components, and I know he had the wind gauge serviced before I rescued it. The radar might be original, but don't know for sure. The monitor comes on, but has never found any objects. This weekend, I opened up the navpod and found that the power and transducer cables were securely plugged in. However, the seatalk cable was left disconnected. I assume the seatalk cable is only necessary to connect the other instruments. Is there any reason to believe that a disconnected seatalk cable is related to radar not finding any targets?

I'm trying to tackle the low-hanging fruit before attempting to investigate the mast-mounted radome, and honestly don't even know if this old equipment is worth too much trouble.

 

[sailingdog]

Have you actually checked for power at the power cable at the radome. If there's no power there, it could be the reason. Plugging in the seatalk cable probably won't hurt, but probably isn't necessary either.

 

[Tim R.]

I have only ever used Furuno and Garmin radar but both of them did not pick up objects on startup. They first needed a minute to warm up and then a command to start scanning. Download the manual from Raymarine to see if you missed something.It could also be that the magnatron needs to be replaced if fairly old.

 

[sailaway78]

Standby

Most radars start up on standby, till they warm up, and then you have to manually turn them on to transmit. Takes a minute or twol When the monitor comes on I think you should see some basic info, and not any objects untill it warms up and is turned on to scan. Would not think the sea talk cable would have any effect on this, but it certainly won't hurt anything to plug it up.

 

[Banooma]

I've left the monitor on for an hour at a time without finding anything, so I don't think it's a matter of patience. It starts with a standby 70 second countdown, and then just sits. I have not yet checked power at the radome itself. Would the power to the dome be independent from the power to the display? Is it common for a 10 or so year old magnatron or radome (are they the same thing?) to die?

I'm not interested in making a heroic effort to save this, but I don't want to dismiss it without at least trying.

 

[sailingdog]

Just because the display powers up, doesn't necessarily mean the radome is getting power.

 

[Maine Sail]

Dumb question but...

This may be a dumb question but after the 70 second warm up did you hit the TX button for transmit???

 

[Rich Stidger]

Hidden display diagnostics on RL70HSB

I have the Raymarine 4Kw radome with a RL70HSB display head. There is a diagnostic mode that you can enter that will tell you some information about the system and will give clues as to what is working and what is not.

The diagnostic are on a HIDDEN Menu. See instruction below to access. The data that you see below is MY data but is typical of the values you should see.

Hope this helps you.

RL70HSB Display Hidden Menu​

Per Mark at RayMarine, 12/06/2002:

To access the hidden diagnostic menus:

Press Menu, Radar Setup, push and hold Enter
Select from the 4 softkeys:

Built-InTest

See next page for typical data

Seatalk Data

This produces two columns of data for Received Data and Transmitted Data. It is hex data and will vary. The data can be paused by pressing the active softkey.

NMEA Data

This produces two columns of data for Received Data and Transmitted Data. It is hex data and will vary. The data can be paused by pressing the active softkey.

EOL Test

This test produces vertical lines on the screen to test for display driver and LCD display problems.

Built-In Test

Diagnostics Menu:

Scanner Build Std 0192824-04D-24-35601-300
Scanner SW Version 03 00
ESN 98120026-L70-00000000-338
Display SW Version SL70 3.38
Scanner Size 24”
Modulator Power 4kW
Heater Hour Count 838.8 (This value should increase from previous values)
Display Comms PASS
Cable Test Status PASS
Receiver Supply 12V PASS
Receiver Supply -5.9V PASS
Receiver Supply 5V PASS
Scanner Reset 0 Times
Ship Heading Sensor PASS
Magnetron Heater PASS
EEProm Write PASS
EEProm Read PASS
Factory Setup PASS
IF Tuned PASS
Modulator Current SP 94
Modulator Current MP 108
Modulator Current LP 89
Rotation Time 2460 ms
STC Preset Max 153
Transmission ON


--------------------- End of data -----------------------------------

 

[Banooma]

Did I hit the TX button? I have to believe so. The radar system not functioning was a big point of contention and negotiation when I bought her. Neither the owner, nor the Catalina dealer-broker was able to get it to work. I presume that both guys had a vested interest in demonstrating that it actually works because they both lost money on the deal by it not working. I also assumed that between them, there was sufficient knowledge to hit the TX button, and make it work. Is it possible they didn't know? Yes, definitely.

I tried a number of different things last year, so I'll check my notes.

I fully realize the radome might not be getting power. I am trying to assess the easier check points first. How would you go about verifying that the radome is receiving power?

 

[Maine Sail]

Did I hit the TX button? I have to believe so. The radar system not functioning was a big point of contention and negotiation when I bought her. Neither the owner, nor the Catalina dealer-broker was able to get it to work. I presume that both guys had a vested interest in demonstrating that it actually works because they both lost money on the deal by it not working. I also assumed that between them, there was sufficient knowledge to hit the TX button, and make it work. Is it possible they didn't know? Yes, definitely.

I tried a number of different things last year, so I'll check my notes.

I fully realize the radome might not be getting power. I am trying to assess the easier check points first. How would you go about verifying that the radome is receiving power?

If the dome is on the mast the first place I would check would be the connections at or near the mast base. With a mast mount the cable must be cut and spliced at the mast base. These are fragile wires that will corrode quickly in that environment. I would completely undo and redo the mast base connections. While you are there you can easily put a clamp on DVM on the power wire to make sure the dome is getting power, at least to the mast base.

 

[Banooma]

Thanks, Rich. I was hoping there was some kind of diagnostic that could be run from the display. I'll try it out as soon as I get the chance!

John

 

[Banooma]

If the dome is on the mast the first place I would check would be the connections at or near the mast base. With a mast mount the cable must be cut and spliced at the mast base. These are fragile wires that will corrode quickly in that environment. I would completely undo and redo the mast base connections. While you are there you can easily put a clamp on DVM on the power wire to make sure the dome is getting power, at least to the mast base.

Thanks Maine. I appreciate your insight. This may be a dumb question, but I'm assuming you're referring to cables that are spliced inside the base of the mast, and this would require stepping it down?

 

[Tim R.]

Any connections inside the mast for a mast mounted radome should be accessable while the mast is stepped as they need to be disconnected before the mast is unstepped. You should have a junction box in one of 3 possible places. If deck stepped then near the base of the mast inside or outside the boat. If keel stepped then either in the headliner near the mast or in the bilge.

There is a piece of coax that goes between the radome and controller. Manufacturers do not want you to splice this but you have no choice. If you are not extremely carefull with connecting this cable, the radar will not work as you have described.