TM260 vs TM270 - which should be the better for fishing 40 - 4000M?

[thylacene]

Having finally worked out how to use our sounder effectively (able to distinguish some species, and locating both bait and fish when prospecting) and with some offshore experience, have decided to purchase a 1kw transducer. While I am very happy with the current transducer, I would like better deep water results.

From what I have been able to glean, the difference is that the 270 has a 20 degree 200 hz beam angle, with the 260 having a 6 degree beam angle.

We usually fish in anything from 40 metres out to where either won't see a bottom.

There is some $450 in price, so trying to determine if it the wide beam is worth the extra extra coin.

I can see merit in the wider beam in some scenarios, and not in others.

Your thoughts?

[juggernaut]

Beam angle on the 270 is actually 25 degrees as per the attached link.

http://airmartechnology.com/uploads/...t_pc_rA_lr.pdf

Refer page 2 of the attached link and I would think the beam diameter is too wide after around 100+ metres...at 122 metres it is 55 metres wide on both frequencies.

A good all round alternative would be to run both a P66 and a TM260 with an airmar switchbox (SB260 or the later SB646) which would all come in at around the price of a TM270 alone. P66 for the shallower stuff and TM260 for the deeper stuff. Cheaper alternative run both transducer cables to your 750s and plug and play as required.

[DaveNkelly]

Would you say that the tm260 isn't very good for shallower water?

what depth are you talking with what tranny?

Cheers Dave

[juggernaut]

Best if you have a look at the beam diameter vs depth and judge for yourself as it will depends on the depths you mainly fish at - see tables on the second page of above link for these comparisons accross the different airmar transducers.

For example TM260 10m/3m at 30 metres depth vs P66 25m/6m at same depth, and so on. So if you fished at 30 metres you would go for the P66 and wouldnt bother with the TM260.