The electronics box is made of wood. Is there an external antenna available for the 1870? I cannot imagine the unit being able to pick up a signal in an enclosed box.
I agree, you should try it before worrying about buying an external antenna.
External antennas are low cost and widely available (GPA017) coming with a 10 meter cable attached.
Thanks. I'll try it using the internal antenna first.
Another question: Is there a plain old 1870 and not the 1870F? I'm not interested in the fish finder feature.