Multiple sonar transducers

[Maxsonsmith]

I have a new Vulcan 12 that I have hooked up to a B744V transducer. The Vulcan also has native compatibility with their Forward Scan sonar transducer, and I am wondering how (or IF) it works with both sensors? Does the normal transducer connect to the "sonar" port and the forward scan to the nmea2k backbone? Vice-versa? Not at all?

Thought someone here more salty than I am might have the answer. I was going to call B&G tech support this morning, but they are M-F. Thanks!

[SV Tru]

I am having dual transducers installed in my Zeus3 system boat. Zeus3 has nmea and dual sonar inputs , one is specified for forward scan. Don't know about Vulcan or b744v transducer.
Something else to consider is the two transducers require minimum 24" separation, I believe.
Another point is to take the abilities of the forwardscan at face value. I have been warned it has limitations, hence the second typical transducer. But you are probably aware of this already.

Tech support will confirm. This info is provided to raise your hopes up during the support dead zone that is the weekend. Lol

[noelex 77]

I installed two conventional (not forward scan) depth transducers on both my current and last yachts.

In both cases they were about 8 inches apart and these work without any apparent interference. However, it is important to select units with different frequencies.

I am not sure how the forward scan operates. If it has a variable frequency there is likely to be a clash of frequency with the second unit. On the other hand, it is directing most of the energy forward rather than down. I think it is probably a question best answered by the manufacturer.

[a64pilot]

Most units I believe are dual frequency and off of memory are maybe 50 and 150 Hz. Units being plotters and fish finders, simple depth gauges I’d guess would be 50 Hz.
Higher frequency gives much better resolution, but loses out in deep water, to work in really deep water go for the lower frequency.
But who cares if it’s 300 ft or 1000 ft?

I thought the newer B&G units the forward scan connected directly to the unit. My older Zeus touch requires a separate box I believe

[noelex 77]

Most of the simple depth transducers operate on a frequency of 200khz. The simple fish-finder transducers can operate on both 50khz and 200khz.

However there are some simple depth transducers deliberately made with a slightly different frequency (usually 235khz) so they can be used with other transducers without causing interference.

Originally Posted by a64pilot

Higher frequency gives much better resolution, but loses out in deep water, to work in really deep water go for the lower frequency.
But who cares if it’s 300 ft or 1000 ft?

Deep performance can be helpful. Depth does provide a useful position line to confirm the GPS position and that the GPS is working correctly. This can be a useful check if out of sight of land. A constant reading rather than series of dashes also shows the unit is operating normally. Depth transducers that only have a very poor range (such as 60m) can be frustrating. In some parts of the world you need to be well into an anchorage before there is any reading at all.

The deeper capacity is one of the reasons to fit a fishfinder rather a traditional simple depthsounder if you only have one transducer.

[GordMay]

Originally Posted by noelex 77

Most of the simple depth transducers operate on a frequency of 200khz. The simple fish-finder transducers can operate on both 50khz and 200khz ...

Indeed.

Dual band transducers generally operate at Frequencies 50 and 200 kHz.
Lower frequencies generally have greater penetrating power, while higher frequencies offer higher resolution or detail. A low frequency around 50 KHz is excellent for displaying a wide area of the bottom, especially if the water is deep, while a higher frequency shows more bottom detail in shallow water.
As a general rule, lower frequency and a wider beam (50° cone) angle tend to go together, while higher frequency and narrower beam (10-15° cone) width are usually companions. This makes sense, as the latter (200 kHz, 15°) makes a great depth sounder, while the former (50 kHz, 50°) is an obvious choice as a fishfinder.