transducer output

[narooma]

I am just updating my depth instrument display but would like to avoid cutting another hole in the hull for the transducer. The existing transducer works buts its output is 175 khz while the new display head is 200. It appears to work correctly in the marina. Can anyone explain where the problem(s) may be (if any) as I am told that the two units are not compatable.
Thanks in antisipation.

 

[Danny]

I would guess that the sensitivity would be affected if the transducer is driven at the wrong frequency. Probably works OK in the marina because it's shallow.

Are you sure you need to drill a hole? The in-hull kits seem to work fine with GRP hulls. You can make up your own fairly easily with a short length of plastic waste pipe, some filler and some suitable oil. You can check that the transducer will work in-hull by just sticking it to the hull with a pad of plasticene or blu-tak.

 

[pau1gray]

Once again with Training Manager for Sonar Company's Hat on.....
Danny has it right. The transducer is designed to operate optimally at 200Khz. This means that it is made to transmit best at 200Khz and receive the same signal at 200Khz. Using the transducer off frequency has two effects:-

1) The power output of the transducer will be lower as you are slightly off frequency - this will therefore affect you maximum range.

2) The reception beam and also amplification of the received will also be affected again causing the system to have a less significant maximum range.

So it will work OK in a marina, but you will find in deeper water you will have problems, as well as that any noise from your engines etc will also affect performance worse than before.
It will not affect the depth measurements as the sound still travels through the water at the same speed regardless of the frequency.

 

[narooma]

Danny and Paul. Will run the new heads in tandem with the old system and old transducers and see how it goes. with thanks