Troubleshooting sounder vs ducer

[Portage_Bay]

Garmin GPSMap 840xs with Airmar B150M 95-155 Khz.

I've been getting errors about ducer not connected. First time it happend was after it had been running for hours. Each time I run it the time from startup to error gets shorter.

The contacts look good but I've unplugged and plugged in multiple times in an attempt to scrape off any unseen corrosion. I've looked for damaged wiring between unit and ducer. Nothing obvious found.

Due to the behavior of the failure I suspect the electronics are failing in the 840. But I'm a long way from being an electronics tech and am just guessing.

Would like to know for sure which end is failing, sounder or ducer. The 840 can be found used or a newer unit compatible with the ducer can be purchased. Replacing the ducer requires haul out.

Any ideas on how to troubleshoot greatly appreciated.

 

[O C Diver]

Find a source for the transducer that allows returned merchandise. Connect the cable and turn it on. If your still not sure, hold it in the water maybe an inch below the surface. If it works, you need a haulout. If it doesn't, return the sender.

Ted

 

[Portage_Bay]

Good idea. My term for that kind of process is brute force troubleshooting. Should have thought of it myself. But I'm in salt water. The odds of being able to return the ducer are not good. Maybe there is a way to fresh water test. As far as I know, and that isn't much, the ducer needs to be in water to function and not risk overheating. A 5 gal bucket would work. Not any kind of a test on accuracy, gain etc but that isn't the problem because when it works it works well.

 

[O C Diver]

Good idea. My term for that kind of process is brute force troubleshooting. Should have thought of it myself. But I'm in salt water. The odds of being able to return the ducer are not good. Maybe there is a way to fresh water test. As far as I know, and that isn't much, the ducer needs to be in water to function and not risk overheating. A 5 gal bucket would work. Not any kind of a test on accuracy, gain etc but that isn't the problem because when it works it works well.

Maybe wrap it in plastic kitchen cling wrap, and zip tie it around the cable, and then partially submerged it in a 5 gallon bucket of fresh water.

Ted

 

[CharlieO.]

My transducer just said to put it a ziploc bag with water to verify operation.