Quote Originally Posted by Larry3215 View Post
Excellent tips! Makes me wonder what the Humminbird ones are made of.
They should be very similar to a Fair Rite 31 Mix Larry.

http://www.fair-rite.com/product/rou...es-2631803802/

I just got 4 of these in today, I am hoping to get them on & do some OTW testing soon, but it's been miserably windy, cold, wet and sloppy here lately.

These are considerable larger that the ones from HB (so I can get more turns wound) and are not sealed or coated with anything yet.

I think I saw them on Amazon for about $15 a pop TYD and there are a lot of sources online.

I don't think I would use the ones cactus flyer was linking myself, since the sonar operates in those frequency ranges and may raise impedance high enough to possibly cause damage to the final output stage of the unit's transmitter.

Data sheet:
http://www.fair-rite.com/wp-content/....php?pid=19348





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