Transducers - help!

[pongoglo]

I am looking to purchase a Garmin combined chart plotter/sonar, but it doesnt come with a transducer. i already have a NASA sounder and transducer fitted. Can I simply use the same transducer/cable and connection, or are transducers brand specific?

 

[Aja]

Welcome.

I think the Garmin accepts data via NMEA. Don't believe the NASA transmits this.

Sorry

Donald
On my Garmin 182 plotter/sonar the only way to get sonar ro work is through a NMEA connection

Donald

 

[bedouin]

The transducers come in a couple of different varieties depending on the frequency the sounder uses (I think the common frequencies are 150kHz and 200kHz - although 400kHz is also used). Transducers will be interoperable provided the devices operate on the same frequency.

Connectors may well be different but it is possible to change the connector on the existing cable.

An added complication is that some transducers sense more than one thing - so the Garmin depth transducer may also detect the water temperature. If that is the case then connecting it up to the old transducer will be more complex as you will have to work out which wires to use, and you would loose the temperature sensing capability

 

[Gordonmc]

Google on Airmar who make transducers used by the majority of instrument makers. On the website you'll find a link to a PDF which gives chapter and verse on what transducers will work with what systems.

My boat came with Stowe Dataline kit and an Airmar B477 tridata transducer. No wonder the stuff never worked. By reference to the chart I was able to buy an instrument head that would work with the through-hull.

Hope that helps.

 

[pvb]

Maybe...

For best results with sonar on Garmin units, you really need a 50/200 kHz dual-frequency or dual-beam transducer. However, the Garmin 398/498 models for example will work with a 200kHz single-frequency transducer, although the results won't be as good. I suspect that NASA use a 150kHz transducer (they certainly do on the Stingray sounder), so I don't think your existing sounder will work with a Garmin unit. First thing to do is call NASA and ask what sort of transducer was supplied with your NASA sounder - if it's 200kHz then give it a try.

 

[npf1]

Re: Maybe...

If it's any help Airmar do a triducer (speed/depth/sea temp) that outputs NMEA.

 

[duncan]

Re: Maybe...

cant see a GArmin unit accepting and diplaying a full sonar record from nmea message.

Might give you the depth figure but why bother if you already have a working NASA depth unit?

Just get the appropriate Garmin transducer to plug into your unit if you want a full sonar picture.

 

[pongoglo]

Re: Maybe...

Thanks to all those who have contributed advice. I purchased the Garmin 198C primarily because I wanted an all in one unit for cockpit mounting, and it is on offer at the moment at www.marinesuperstore.com. Having a twin keeler, I wanted to be able to 'see' the bottom, before I set her down.All those who advised that the NASA transducer wouldnt work were of course right. I have resolved the issue by purchasing an AIRMAR In-hull P79, which works very well, and will retain the NASA sounder as a backup system.