Campbell Scientific AL200 ALERT2 Encoder, Modulator, and Sensor Interface User Manual

Page 19

AL200 ALERT2 Encoder, Modulator, and Sensor Interface

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Set the

Slot Length – This is the maximum amount of time within the

frame that the station can report during. It is an integer value between

500 and a maximum of the

Frame Length.

•

Set the

Slot Offset – This is the amount of time into the frame that the

slot will occupy. For example, if your frame is 120,000 ms (2

minutes) and your slot offset is 60,000 ms, the slot time will begin 1

minute after the beginning of the frame.

•

Set the

Hop Limit – (None) – This is the maximum number of times a

remote transmission can be retransmitted by repeaters.

•

Set the

Path Service Enabled – (No) – When enabled each device

that repeats a remote transmission will add its source address to the

packet. This makes it possible to trace the path that a packet took

from its beginning to its destination.

Radio Settings

The default radio settings have been chosen to work well with Campbell

Scientific’s RF320 series (Ritron DTX-L series) radios. If using a different

type of radio, consult the manufacturer and apply the changes to the following

settings.

•

Set the

Radio Power Up Mode – (On Only With Data to TX) – This

determines when the radio will be powered on.

•

Set the

Radio Warm Up – (750) – This is the amount of time, in

milliseconds, that power will be applied to the external radio prior to

data transmission.

•

Set the

Carrier Only Time – (10) – This is the amount of time, in

milliseconds, that radio will be fed an unmodulated carrier.

•

Set the

AGC Time – (25) – This is the amount of time, in

milliseconds, that the radio will be fed a tone-modulated carrier.

•

Set the

Tail Time – (5) – This is the amount of time, in milliseconds,

an unmodulated carrier will be transmitted following data

transmission.

•

Set the

Modulation Voltage – (390) – This is the peak-to-peak

voltage level of the modulated signal that will be fed to the radio.

Value is expressed in millivolts.

•

Set the

Modulation Polarity – (Normal) – This is the polarity of the

modulated signal fed to the radio.

GPS Settings

•

Last GPS Fix – This is the data and time of the last successful GPS

fix obtained by the AL200.