Wood and Douglas 1335, Operating Instructions Manual

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1892 1335 - Orion Radio Modem Operating Instructions - v2.9 / Aug 2009
REPEATER CONFIGURATION
A repeater serves a single group, relaying User Data or telemetry messages which it receives
without alteration of any kind. The group must use addressing (i.e. not GroupID 0). It prevents
proliferation of messages by maintaining a list of messages already relayed, which it ignores.
Broadcast messages with the DestID 255 are relayed, but messages with a GroupID of 0 are
ignored.
v All Orion units maintain a list of recently received messages, and discard
duplicates.
Mode R Parameters
Unit ID
(ATS170)
The Repeater’s UnitID is only used if it sends an alarm message, since
it simply relays all incoming messages. It may normally be any value
from 1 to 254 provided it is a unique address within the Group which it
serves. However, if the group is working on Mode L, it should be higher
than any Outstation, so that it is not polled.
Dest ID
(ATS171)
Not used, since the repeater never initiates a transmission.
Group ID
(ATS169)
The same as all other units within its Group, 1 to 254. The value of 0 is
invalid; repeaters cannot be used in groups without addressing.
Over-air mode
(ATM0)
This must be the same as the rest of the network which it serves.
Repeaters cannot be used with Packet (TP) protocol.