Most of you might be familiar with my previous posts on problems I was having with erratic readings from my Furuno fishfinder; the Furuno 620
I had written to airmar customer support about these erratic readings, and I am reproducing the emails herein:
Question to Airmar:
My Airmar B744V Thru hull is linked to the Furuno 620. I've had it for 3 years without any problem. This year, the bottom depth reading is very erratic, even in shallow depths of 3 metres, and the bottom line shown on the screen is all dotted, as opposed to the solid thick line I was accustomed to. Any reason why this is happening. I have always followed the instructions on cleaning the transducer face as outlined on your site.
Answer from Airmar:
Thank you for contacting AIRMAR Technology Corporation. The transducer is a simple device with wires attached to the ceramic element. Something would have had to physically happen to the wires or the ceramic for it to fail.
There truly isn't a way to test a transducer using a standard voltmeter. You would require an oscilloscope and a signal generator or an EDI test box to properly test both the transducer and the fishfinder.
The most common, reliable test on the boat is to connect a new transducer to the fishfinder and hang it overboard to verify operation. A local marina may offer this as a service provided you do not harm the transducer in anyway.
If you require any further information, please do not hesitate to contact back.
Well, I went along to Medcomms, local agents for Furuno, and spoke to Mark about my problem. I also informed Mark about my email and answer from Airmar. Without hesitation, Mark kindly provided a spare transducer for me to try out. No questions asked, no hassle, he didn't even want a deposit or my ID number. I must commend this excellent customer support and service. Went to the marina, hooked up the new transducer, and got the same erratic readings
So, there was nothing left for me to do then just activate the factory reset facility on the reciever. Presto, the Furuno was working fine again. Instant readings, accurate, and back to its optimal functionality.
Great stuff, great customer support.