V
IA
L
ITE
HD-B
LUE
2-L
INK
-H
ANDBOOK
-HRX-XX-8X-35-XXXXX
12
2.3
Using the RF link module
2.3.1
Connecting the module
Connect the transmitter module to the power source, cross-site fibre optic cable and RF signals. The
RF input signal applied to the signal connector should be within the maximum and minimum signal
levels given in the datasheet.
2.3.2
LED indicator, purple modules
These modules are fitted with a single LED for indication of the state of the module.
2.4
Module Interface ratings
2.4.1
Susceptibility to DC pulses from ViaLiteHD receivers
All receiver modules will create a 1-
2Vpeak DC transient from the RF output at start up into a 50Ω
load (approximately 5V into a 1MΩ load). This may cause failure in some very sensitive spectrum
analysers or similar equipment. Please check before connecting your equipment. Contact
ViaLite
Communications
for more details.
2.4.2
Protection of ViaLiteHD equipment from DC pulses
All modules have AC coupled inputs and/or outputs and will be sensitive to large transients (>5V)
applied at the RF connector. This may result in permanent damage to the modules, particularly to low
frequency or wideband modules. DVB-T and L-Band HTS modules are designed to survive non
repetitive DC pulse of up to 36V. To increase protection, BUC feed option “B” can be specified for
GPS receiver modules to increases their robustness to DC pulses contact
ViaLite Communications
for more details.
2.4.3
Logic interface, TTL 5V
Absolute maximum voltage rating
-0.5 to +5.5V
No damage
Input, Logic Low (max)
<0.8V
Input, Logic High (min)
>2.0V
Output, Logic Low (max)
<0.4V no load
Output, Logic High (min)
>4.8V no load
Drive capability
1k ohms
Short circuit protection
No
Colour
Blue link
LED
GREEN
Normal
RED
Alarm
No Light
No power
LED
