Installation Guide

Table Of Contents
Task 4: Configuring General and Unit settings PMP 450i and PTP 450i Configuration and User
Guide
Attribute Meaning
timing port and the power port, the power port GPS source is
chosen first.
If there is a loss of GPS synchronization pulse, within two
seconds the AP automatically attempts to source GPS signaling
from another source. On-board GPS (internal GPS) is the last
source checked for GPS signaling if there is no receipt of
signaling from the timing port or from the power port (the on-
board GPS module must not be used as the primary timing
source). If no valid GPS signal is received, the AP ceases
transmission and SM registration is lost until a valid GPS
signal is received again on the AP.
AutoSync + Free Run: This mode operates similarly to mode
“AutoSync”, but if a previously received synchronization signal
is lost and no GPS signaling alternative is achieved (from the
timing port, power port, or on-board GPS), the AP
automatically changes to synchronization mode “Generate
Sync”. While SM registration ins maintained, in this mode
there is no synchronization of APs that can “hear” each other;
the AP will only generate a sync signal for the local AP and its
associated SMs. Once a valid GPS signal is obtained again, the
AP automatically switches to receiving synchronization via the
GPS source and SM registration is maintained.
In mode AutoSync + Free Run, if a GPS signal is never
achieved initially, the system will not switch to “Free Run”
mode, and SMs will not register to the AP. A valid GPS
signal must be present initially for the AP to switch into
“Free Run” mode (and to begin self-generating a
synchronization pulse).
Also, When an AP is operating in “Free Run mode, over a
short time it will no longer be synchronized with co-located
or nearby APs (within radio range). Due to this lack of
transmit and receive synchronization across APs or across
systems, performance while in Free Runmode may be
degraded until the APs operating in “Free Runmode
regain a external GPS synchronization source. Careful
attention is required to ensure that all systems are
properly receiving an external GPS synchronization pulse,
and please consider “Free Run” mode as an emergency
option.
Generate Sync (factory default): This option may be used
when the AP is not receiving GPS synchronization pulses from
either a CMM or UGPS module, and there are no other APs
active within the link range. Using this option will not
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