Hardware manual

TVI I300 Hardware Manual © Essential Viewing Systems Limited 2010
Page 8
4.2 Cellular RF Antenna – J9
The I300 includes an onboard cellular modem which requires an external RF antenna to operate.
The antenna connector on the I300 is an SMA socket labelled as J9.
The connection from J9 to the external antenna must be via coax with a 50 ohm per meter
impendence. If the link to the antenna is routed through a bulkhead connector then this
connector must be a 50 ohm coax RF connector where the body of the RF connector is grounded
to the enclosure. The internal linkage from J9 to the bulkhead connector must be 50 ohm coax
and a 50 ohm SMA plug must be used. It is vital that the connection between the coax cable
and the bulkhead connector maintain the integrity of the coax shielding.
Failure to use the correct coax cable and connectors will result in poor cellular performance and
is likely to cause undesirable EM interference and potentially damage to the modem.
4.3 Audio Inputs/Outputs – J21
The I300 provides dual channel line in audio and dual channel line out audio on header J21
where inputs and outputs are at line level. The following table specifies the mating connector
and connector pins.
J21 – 5x1 JST PHR connector
Description Pin
Audio left input 1
Common ground 2
Audio left output 3
Audio right input 4
Audio right output 5
4.4 Power Input – J23
The I300 is powered via J23 where an input voltage in the range of 9v to 36v DC is supported.
The following table specifies the mating connector and connector pins.
J23 – 2x1 Molex Micro-Fit header 3.0mm pitch
Description Pin
+DC supply 1
0v (chassis GND) 2
Note that while the I300 board incorporates a filter on the DC input it may be necessary in some
circumstances to utilise a common mode choke on the power input to suppress induced
electromagnetic interference and DC-DC switching noise. Where a choke is utilised within an
enclosure it is important to minimise the length of the cables between the DC input socket and
the choke.