[CA] [CA11] Selecting a MFD Transducer & Radar

[SeanStewart]

I am looking to upgrade the electronics on my boat and seek advice. I intend to purchase 12" MFD, transducer, AIS radio and radar to replace my existing equipment. Existing equipment includes radar, radio, GPS, and fish finder w/ thruhull fairing block transducer (all very old ~90's)

I am located in Santa Barbara, CA and am a recreational fisherman. We primarily fish the offshore islands for calico, yellowtail and white sea bass (0-100'), blue and yellowfin tuna (0-250'), and rock cod (0-500').

About my boat: 25' Skipjack Fisherman, fiberglass hull powerboat, diesel inboard w/ outdrive, 18 degree deadrise. Kept on trailer.

I believe the following selections are appropriate, please confirm:
Ray73 VHF Radio with GPS, AIS Receiver and Loudhailer Output
Quantum Q24C 18" Radar with 10m Power and 10m Data Cable
GA150 GPS & Glonass antenna for direct connect to AXIOM Pro and AXIOM XL
12" MFD and transducer (please advise on MFD and transducer inquiries below)

Transducer - currently use thruhull w/ fairing block positioned in forward / starboard quadrant of bilge. My goals are to buy one transducer (bronze), utilize the existing thruhull (if possible), and get a more low profile design due to the small size of my boat (e.g. non fairing block). At a minimum, the transducer must provide depth, temp, wide scanning and high quality sonar for finding fish in the 0-500' range. I am interested in the down, side, and 3D vision capabilities, but these are not essential.

Q1: When dealing with deadrise, are two transducers required to utilize down, side, and 3D vision capabilities? If so, I will likely forgo these capabilities.

Q2: If two transducers are required per Q1 above, is B175H-W w/ 20` deadrise (#A80321) the best singular transducer for me conceding that I will not be purchasing down, side, and 3D vision capabilities?

Q3a: If not B175H-W w/ 20` deadrise (#A80321), what else would you suggest?

Q3b: Due to increased cost associated with B175 low/high or med/high I am less interested in these models and am not sure if dual channel chirp is necessary for my needs. Please advise.

Q4a: If B175H-W w/ 20` deadrise (#A80321) is best for me, what 12" Axiom MFD do I need: Pro S or Pro RVX

Q4b: If not B175H-W w/ 20` deadrise (#A80321), what MFD do I need?

Thank you,

Sean

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Sean,

General comment: The equipment list appears to be good. If supplied with a photo of the currently installed transducer's identification tag, then it may be possible to identify whether it may be adapted for use with one of Raymarine's currently manufactured fishfinding products.

Q1: When dealing with deadrise, are two transducers required to utilize down, side, and 3D vision capabilities? If so, I will likely forgo these capabilities.
A1: Unless the vessel features a flat on the keel which is as wide as the 0 degree RV transducers (4.15"), then a pair of tilted element RV transducers would be required to support these sonar features.

Q2: If two transducers are required per Q1 above, is B175H-W w/ 20` deadrise (#A80321) the best singular transducer for me conceding that I will not be purchasing down, side, and 3D vision capabilities?
A2: This indeed sounds like a good fit for this application depths specified. According to the information from Airmar, this transducer will typically support a maximum depth from 600' to 800'.

Q3a: If not B175H-W w/ 20` deadrise (#A80321), what else would you suggest?
A3a: I would go with the B175H-W.

Q3b: Due to increased cost associated with B175 low/high or med/high I am less interested in these models and am not sure if dual channel chirp is necessary for my needs. Please advise.
A3b: I would agree, particularly given the depths of operation, type of fishing, and as you only want to install a single low profile transducer.

Q4a: If B175H-W w/ 20` deadrise (#A80321) is best for me, what 12" Axiom MFD do I need: Pro S or Pro RVX
A4a: The Axiom Pro S may only be mated to a CPT-S transducer. Therefore, an Axiom Pro RVX MFD must be installed.

Q4b: If not B175H-W w/ 20` deadrise (#A80321), what MFD do I need?
A4b: An Axiom Pro RVX MFD or an external high power CHIRP sonar module (ex. CP470, CP570, RVX1000) must be installed to utilize any high power CHIRP transducer.

[SeanStewart]

Thank you Chuck!

I plan to purchase the B175H-W and Axiom Pro RVX MFD.

Follow up questions:

Do I need to order any extension cables?
-online recommends pairing w/ CHIRP Transducer Extension Cable
-Or an RV to DV transducer cable? (A80490)

Thank you

[Chuck - Raymarine - Moderator]

Sean,

Q. Do I need to order any extension cables?
A. Yes. All wide beam products come with a 2M pigtail off the transducer. Pair with a CHIRP Transducer Extension Cable (3m (A102148), 5m (A102150) or 10m (A80327)) for a complete transducer installation. As only the B175H-W will be installed and it only supports high frequency CHIRP operation, an A80328 Single B75/B175 Operation Cable will additionally be required.

[SeanStewart]

So I received my new transducer today (Airmar B17HW) and as soon as I open the box, first thing I see is a neon green piece of paper titled "AVOID OVERHEATING install at a cool location away from the engine."

I run a 25 Skipjack Fisherman with an inboard diesel (TAMD41). First, I was hoping to reuse the existing thruhull in the starboard/forward corner of the bilge. Second, due to the layout of this boat, there is literally nowhere else I could locate the transducer other than the engine compartment/bilge, unless I step out further away from the keel and past the lift strake. This is also not ideal to due increased opportunity for cavitation as you move further away from the keel.

So my questions are:

Is there a specific temp that has been identified to cause the transducer to fail? I'm considering using another object to test the temp range with engine warmed up. Running in cool California water has got to help dissipate the heat sink on the ducer.

Have folks installed a B175HW in close proximity to their inboard? Issues or experience?

Alternatively, should I not be worried about performance issues with a new thruhull outside of the lift strake?

Also picked up a transducer collar from this company down in Australia to get the unit just a little further away from the hull. Do you have input on these?
https://qmeq.com.au/product/1kw-transduc...lar-qme01/

Thank you

[Chuck - Raymarine - Moderator]

Sean,

Airmar, Inc. produces the high power CHIRP transducers for Raymarine. I would recommend contacting Gemeco, Inc. (Airmar’s US distributor (803 693 0777)) directly regarding both of these questions. Alternatively, Airmar, Inc. ((603) 673-9570) may be contacted for guidance.