Thales 421, Operation And Maintenance, Page: 76 / 256

LLZ 421
Operation Operation and Maintenance
ILS 420
3−10
Ed. 01.07 SOAC
3.4.3 Monitoring ATIS or Voice and Use of local Voice Input
If the ATIS or voice input capability of the optional VAM−ILS is used, the output signal can be con-
trolled by a connected headphone: Use a standard headphone (min. 32 ohm impedance) and con-
nect it to the upper 3.5 mm jack at the front of the VAM−ILS board.
If a message shall be initiated and transmitted locally at the station, connect a standard microphone
(600 ohm impedance) to the lower 3.5 mm jack at the front of the VAM−ILS board. Switch S1 at the
front of the VAM−ILS board in the upper position to enable the microphone input.
3.4.4 Functional Check of Indications
When the two middle buttons of the control buttons of the LCP (S2 and S3) are pressed simulta-
neously all indications light up simultaneously and the buzzer sounds for optical and acoustical test
purposes. Since the monitor carries out normal checks of function and accuracy, the operation of the
installation is faultless when the liquid crystal display screen of the LCP indicates NORMAL. If however
the display screen shows WARNING or ALARM, a check of the installation via PC is possible if opera-
tion mode LOCAL" has been set by the key−lock switch on the LCP.
3.4.5 Switching off DC Supply
Use switches TX1 and TX2 to switch off transmitter 1 and/or 2. The indications on the LCP extinguish.
NOTE: The LRCI (LCP and modem) is neither switched off via the remote nor the local control
interface, so that it can receive switch−on commands as long as any of the switches TX1
and TX2 are on.
Ed. 07.08