TransCore AR2200, Руководство пользователя

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Installing the AR2200 RF Module
3-5
Required Equipment
•
Voltmeter
•
Oscilloscope, 100 MHz (for monitoring intermediate frequency [IF] signals and
discriminate signals)
•
Data terminal or computer
•
Phillips and flat-blade screwdrivers
•
N-type 50-ohm load (placed at the antenna port for testing)
•
N-type attenuators (as needed to adjust RF power)
Positioning the RF Module
In permanent installations, position the RF module as close as possible to the antenna
and within 1,000 signal cable ft (305 m) of the reader. Long cable lengths will
increase system sensitivity to noise. Coaxial cable runs in excess of 50 ft (15.2 m)
between the RF module and antenna are not recommended.
1
Longer signal cable
connections (up to 1,000 cable ft) (305 m) should be made on the reader-to-RF
module link.
Refer to the reader documentation for further information concerning RF module
positioning.
Terminal Connections
The RF module plug and jack connector pair have 21 terminals. Connections from the
reader are made to the removable plug. After connections are made, the plug can be
removed from the jack for interface board servicing or repair/replacement.
Figure 3-2 shows the RF module terminal connections.
1. Based on 2 dB loss, Andrews LDF4-50A 0.5 in. OD coaxial cable. If 3 dB loss is tolera-
ble, cable up to 75 ft (22.9 m) long may be used between the RF module and the antenna.