I wouldn't go out on Lake O without one. I have a Raymarine unit, bought it on sale for around $150.00. I have a 3' stainless antenna with a coil at the base and unless you are planning to transmit from one side of the lake to the other it works well. I didn't have the available space to fold an 8' fibreglass antenna flat when not in use. I understand that the 4' shakespeare's work well too, although a little pricey.