Humminbird RF40 SmartCast Manual page 2

Channel A and B RSS Units
There are two versions of the RSS that are available: Channel
A and Channel B.
When using the A or B version of the RSS, make sure to
select the appropriate channel for the RSS in the Channel
menu on your control head.
The A or B RSS option is intended to give you the flexibility
to change to a different RSS and channel if another angler is
using a SmartCast product in close proximity.
Note: Using two RSS units of the same channel in close proximity
(100 ft.) will result in severe interference that will prevent the product
from functioning correctly. Using a Channel A and a Channel B within
close proximity to one another will significantly reduce interference
but will not completely eliminate the interference.
Note: RSS units, regardless of Channel, either in close proximity to
each other or to other sonar devices (closer than 40 feet) can also
experience or cause sonar interference, which may result in erratic
depth readings.