APPENDIX 1
LED Indications
The Signal Strength LEDs
are Red and Green. See Fig 1 & 2.
When the DualCom in not triggered, these give an indication of the GSM radio
signal strength received at the DualCom. A ‘once per second’ short off-blink
shows all is OK.
The Signal Strength LEDs will give a signal strength indication after the DualCom
has been powered for 30 seconds (and the NVM has been programmed).
Note that the Red and Green signal strength LEDs (See fig 1) will not operate
with an incorrectly programmed or blank NVM.
Green On, Red Off.
High Signal Strength
Red & Green On.
Medium Signal Strength
Red On, Green Off.
Low Signal Strength
Red Off, Green Off
GSM radio can not hear any base stations,
GSM path fault or signal strength = 0
LED(s) On + short off-blink.
GSM radio can communicate with a
(1 off-blink per sec)
local base station, GSM path status = OK
Power-up / Reset Indications:
When power is applied to the DualCom, the Radio LED will be lit for 10-20
seconds while it registers on to the GSM communications network.
The Red and Green signal strength LEDs will also give the following indica-
tions:
3 red flashes followed
Power-on or Reset in progress.
by 1 green flash
LEDS alternate flash - fast.
GSM network re-registration in progress.
(Red, green, red, green ...)
(On & Off 8 times per sec)
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