Y1-06-0130 Rev. B
Page 5 of 9
2.2 Arming Pin
The arming pin requires a pull force of approximately 8 pounds from an angle of 0 to 60
degrees from the pin axis. The manufacturer of the inflatable device performs
attachment of the lanyard to the raft.
To activate the transmitter, pull the lanyard until the cylindrical arming pin is removed
from the corresponding clip in the transmitter housing. As soon as the arming pin is
removed, the unit is ready to transmit. In the case of the -001 single antenna model, to
begin transmitting, the antenna sensors must be submerged (or moistened fingers
placed across both sensors of the antenna) or the water activation sensor must detect
water. With the -002 double antenna model, transmission will begin when the antenna
sensors are submerged (or moistened fingers are placed across both sensors of one of
the antennas).
Inserting the arming pin back into the clip in the transmitter housing will either disallow
operation or cause an operational unit to cease transmitting. Transmission has stopped
when the LED on the transmitter housing ceases flashing.
2.3 Antenna
The antenna(s) is an omni-directional, vertically polarized, whip antenna. The antenna
assembly consists of a pliant rubber base and a replaceable flexible whip antenna
mounted in a base. The antenna is resonant at 121.5 MHz, 243.0 MHz and 406.028
MHz.
The rubber antenna base features activation sensors that operate by water contact or
other low resistance contact. The base also incorporates a RF ground plane, which
enhances RF transmission when in contact with the raft surface.
2.4 Water Activation Sensor
On the -001 model, a second wire lead from the transmitter case terminates in a low
resistance water activation sensor. This wire lead is generally mounted so that following
normal inflation of the raft, the water activation sensor will be located well below the
water line. This sensor lead is detachable from the transmitter.
On the -002 model, the water activation sensors are on both antennas.
2.5 Battery
Power for the SRB-406 transmitter is provided by a single lithium battery pack that is
located within the transmitter housing. The battery pack uses 4 each
lithium/manganese dioxide, 1-1/4 “C” size cells. The cells are arranged in series. Each
cell is protected from short circuit by a manufacturers installed safety device (PTC).
