Rkatz1

Am installing Simrad NSS Evo2 16" and a 9" on my new Gause. Getting the structurescan transducer but builder was also going to be installing a B60 thru hull transducer.

I questioned him with regards to this transducer bc it is not CHIRP and heard the B175m was a good CHIRP transducer. Builder came back and said the B150m would be better.

Is this the case? Will be mainly fishing inshore/nearshore Tampa Bay and occassionally offshore and once to twice yearly offshore in the keys. I figure if the evo2 comes with built in CHIRP I should take advantage of it.

Question: is he right about getting the b150m as opposed to the b175m? Also... Should I not even bother with CHIRP?

I'm a newbie when it comes to this so please keep it simple.

I have heard that fishing the Gulf coast of Florida does not need CHIRP.

Thank you in advance....

semperfifishing

The B150 is a 300 watt single element...if you fish under 150' it will get the job done.
The next step up is the 600 watt B75...in the Medium version you have a good unit for fishing from shallow to about 500'.
The 1 kw B175 is going to give you added capabilty when going deeper .


So it all depends on your fishing paramaters...

BoemarineBrian

You can run the B175 in non CHIRP for the gulf side if it would make you feel better. I wouldnt agree with the statement that you dont want it. You'll certainly want CHIRP for the Keys and the offshore work. Give me a call at 866 735 5926 ext 120 to discuss further

Rkatz1

98% of my fishing will be in the bay and the gulf in less than 150ft. The only time I go deeper is the one week per year I am in the keys and go to the humps. So it seems the 150m would be the way to go. Would it screw me if I had the 150m and I was in a few thousand feet in the keys, meaning would I not be able to see stuff at all?

I also heard that since Tampa and its surrounding offshore areas are flat and boring and not very deep, that CHIRP is not needed. So.....if I don't really need the CHIRP and can get by with a B60 transducer, let me know.

mahimahi99

Rkatz1,
I just took some screenshots of a couple of reefs in TB, if you want PM and I'll share them with you.
The builder couldn't be more wrong btw, I can also show you the HUGE difference in the B175 v. B150 in air bladder separation of bait fish right off of the skyway. You don't need a Medium frequency transducer out here, you'll constantly be running it in 155kHz so it's better to go with a High Frequency here in these shallow waters or go with the B60.

BoemarineBrian

Well said MAHI you have an artful way with words!

Rkatz1

So you are saying the b175 high frequency would be the way to go??

Rkatz1

He told me the internal CHIRP in the evo2 is single band. Does this make a difference?

I'm not a tech guy. I just want to fish Tampa bay and it's near shore and offshore waters with the clearest image.

Rkatz1

Just pm'd you mahi. Thx.

mahimahi99

I got your PM, but I'll answer here too so that others that may want the same answer.

"So you are saying the b175 high frequency would be the way to go??"
- For this area, yes that would be the best transducer because of the range of frequencies you could tune it to, if you didn't want to CHIRP. I have seen in some cases where running a single frequency you actually get a clearer picture than when in CHIRP, it doesn't happen as much in H frequency as it does with the M frequency. Since you'd have a HIGH you could run on the higher end of the frequency band and still retain a great picture for the depths around here if you did want to run a single frequency. For example, when I can't CHIRP (I have one screen) because I want to run my SS, I have to go to 83kHz. Which at these depths is just really good for locating the bottom and knowing the actual depth, detail not so much.

"He told me the internal CHIRP in the evo2 is single band. Does this make a difference?"
He's correct in the fact that it is a single band but not in the fact that the Medium Freq (and weaker strength) transducer is better than the High Freq (and much much stronger) transducer.

I haven't even mentioned that you won't lose the bottom while running with the B175, with the B150 almost always. Now given that you're running two evo2's, another option would be to run a B60 & B150M. While running (on plane) you'd run the B60 so that you wouldn't lose the bottom (ever) and in shallow water (i.e. less than 20'). For deeper water or slow searching a reef you could CHIRP it with the B150. So the B60 would go to one NSS and the B150 to the other one. Personally I'd stay with the B175H-W. But just another option.

Rkatz1

Holy cow......although u are trying to help, I am getting more confused.

I don't know if I want to lay down the huge $$$$ for the b175. With this, Gause recommended the b150m. I was gonna go with this but now u r telling me I'm gonna lose bottom while running with the 150m? That's crazy! The "regular" bottom finder I had with my old raymarine (I think dsm250) never lost bottom while running.....so why would this higher tech machine lose bottom while running

Now I'm thinking maybe I'll screw it all and stick with the non-chirp b60....

mahimahi99

Sorry, with all the technology and now with all the choices it does get a little much sometimes. But in regards to your old raymarine, you were more than likely running a 500 or 600 watt transducer. The B150m is only a 300 watt transducer which is one of the lowest (if not the lowest) powered transducers made today so that's why it has the inconsistency of holding the bottom at speed. Even my old $80 Garmin transducer was 500 watts and never lost the bottom. But if you don't want to drop the $ on the B175, the 600 watt B75H would be another gteat choice. It's the CHIRP version of the B60, so it won't lose the bottom and you'll still get awsome fish detail too. Again sorry if I confused you, I just think when your spending this kind of money on a system it helps to know what to expect. One thing that some of have mentioned before on this forum but rarely is said at the retail stores or online places, is that your sonar system is only as good as your transducer.

nodoubt

loosing bottom has wayyy more to do with where you put a transducer than power, to an extent

million watt td aint gonna do you no good trying to shoot thru a " bed pillow" worth of bubbles and turbulence

ive got a tm- 150, 300 watt, that can hold bottom all day long at 45 mph, and mark bait and fish while doing it.....

abbor

The combination of relatively low sensitivity and a wide angle give TM150M and B150M challenges when it comes to high speed. B75H is an excellent high speed sensor, when cruising in rough weather I use B75H instead of B175H-W due to the excellent bottom tracking performance of B75H. I also have TM150M so I know how it compares.

Northern_Pike

And I think that the water flow over the TM150 isn't as good as it could be cause of the design. The house of the P66 seems much better in that aspect.

abbor

I agree.

leftcoast

Can you post pics here?

mahimahi99

I agree, in almost all of the cases where you lose the bottom it has to due with alignment and placement, except in the cases that I'm talking about, I went back and looked at my install records since last September (about when Airmar was able to catch up with the demand of the new transducer) and of the 23 TM/B150M's I installed, 7 of them have been replaced with either a B60 or P66, 2 were replaced by HDI transducers (for not only not holding the bottom but mostly because of the ability of not running CHIRP and SS at the same time). All of the replacement transducers were in the same locations as their 150 counterparts. I have a TM150M and love it, but at the same time I know what to expect from it and how to use it. Most of the ones I have either installed or sold the owners are happy with it and don't mind if it loses the bottom from time to time, they run deep enough that they don't care. And notice I use the word "consistently", I've seen it hold bottom for a while then lose it, then come back for a short while then lose it and so forth. So I'm not saying that it won't hold the bottom, just not consistently.

You guys might be right about the design, it does seem to have smaller housing than even the P66. But that makes me even more curious about the B150 because I've seen issues with that one too.

abbor

The cone angle of TM150M and the replacements are not the same, actually quite different (typically TM150 is 2x as wide) so there are more factors than housing style which is influencing the result.

abbor

I strongly recommend a CHIRP transducer for shallow water use even if it mostly will be operated in fixed frequency mode. A B60 (or P66) has a Q-factor of about 30, B75H about 2. The lower Q-factor will result in much less ringing which will significantly increase the resolution.