Fish finder / sounder

[whisper]

We currently have a Simrad sounder in our wheelhouse but are also considering fitting a fish finder on the flybridge. Were told today that we could run the latter off the same transducer cable as the sounder.
Anyone know if this is true as it seems unlikely to us ?
Thanks.

<hr width=100% size=1>

 

[Evadne]

Quite possible, a fish finder is only a fancy echosounder, after all. I'd ask Simrad for the specs (frequency and power) for both items, and the transducer. They may be on their website.

<hr width=100% size=1>

 

[john_morris_uk]

You might be able to - but not at the same time. And remember that the length of cable to the transducer is critical. (ie you can't just 't' a piece of appropriate co-ax off and remember to only switch on one at a time.) The capacitance of the cable is used as part of the e/s or fishdinder and they won't function accurately without the correct length of cable (and hence correct capacitance) plugged into them.

<hr width=100% size=1>

 

[duncan]

Some transducers have twin cables/plugs to facilitate this I believe but if the one already fitted doesn't you are just as well fitting a complete new unit given the prices and constant development in this area. ie if you have to get another Simrad headset and a new transducer...............

<hr width=100% size=1>madesco madidum ..../forums/images/icons/smile.gif

 

[whisper]

This statement was made by a salesman who was trying to sell me a Piranha FF. Don't think this would work by teeing into Simrad cable somehow.

<hr width=100% size=1>

 

[duncan]

can think of just so many reasons it wouldn't work that to even start on why you wouldn't bother..........

<hr width=100% size=1>madesco madidum ..../forums/images/icons/smile.gif

 

[gjgm]

Why would you want to. B/white FF costs sod all, and comes with transducer anyway, and it dead simple to fit. Seems unnecessary to make the job complicated?

<hr width=100% size=1>

 

[duncan]

suspect that tied up in the question somewhere is the vexing question of 'can I run 2 units with the same frequency transducers without interference.......?' Most are happy to say that different frequencies are ok but now that 200 has become so standard (or 200/50) there seem to be concerns. Never seen a definitive response and may well ask Lowrance or similar one day to get one .........

<hr width=100% size=1>madesco madidum ..../forums/images/icons/smile.gif

 

[Evadne]

I hadn't meant to imply you'd be able to run both simultaneously. Transmitting into the Tx output of another device is not recommended!

I'd be surprised if the cable length is critical - it should be properly terminated in the transducer. You can get COTS co-ax switch boxes from the likes of Farnell, I think, though you would need to confirm that the cable is 50-ohm or 75-ohm to use a standard one.

<hr width=100% size=1>

 

[john_morris_uk]

I regret that the design of many echo sounders uses the characteristics of the cable as part of the deisgn - you get false readings if you alter the length - not from transmission time of the pulses I hasten to add!

<hr width=100% size=1>