Specifications

BATS AND PORTABLE BATS OPERATION

3-22

Reply Frequency Setup Parameters: This is the Reply Frequency of the beacon. Select the Re-

ply Type; CW (continuous wave/tone), Shift (linear frequency shifted, also known as chirp or FM),

Coded (special such as Remus codes), M-FSK (multiple- frequency shift keyed; typical for Model

4370A beacons) and PRN (pseudo random number generated codes).

CW (tone)

The CW waveforms are typical of the ORE legacy bea-

cons, Model 4320 or 4330 series (see note below).

The burst is a single frequency with a typical pulse

length of 1.3ms. Select the frequency in 500Hz in-

crements and the correct pulse length

SHIFT

The shift waveforms are a linearly changing frequency

over a specific pulse width. Enter in the start frequen-

cy and the end frequency in kHz along with the exact

pulse length in ms. For example, an Edgetech Model

4200 Towfish with responder option produces a wave-

form starting at 24kHz and ending at 28kHz with a

pulse length of 10.000ms.

M-FSK

These waveforms change frequencies in discrete

steps instead of in a linear progression as in the shift-

ed types. The MFSK codes are shown in Appendix E.

CODED

These are proprietary codes of Hydroid’s REMUS un-

derwater vehicles and transponders. They have spe-

cific interrogation and reply PRN type codes.

REMUS-1

REMUS-2

REMUS-3

REMUS-4

The CW output type beacons such as the Model 4330B as used in the Trackpoint 2 or 3 will not

provide any improvement in performance with BATS. These should only be used in an emergency

not in normal operation.