Chapter 1
Overview
The front and rear panels
4460 GSM System Option and 4468 EDGE System Option
Version 12.20
11
Connectors on the rear panel
The rear panel is divided into three main sections. These are from left to right:
the RF section (1), the PC unit (2) and the Power supply (3). Each section provides
one or more connectors for specific functions. The connectors are described from
left to right and from top to bottom.
Connectors on the RF section
Not all of the connectors may be fitted in your 4400. The connectors actually
available depend on your system configuration, in particular the installed system
options.
EXT SYNC —
BNC socket. Input for external reference signal. If a high-precision
reference signal of 5 MHz, 10 MHz or 13 MHz is connected here, the internal
10 MHz reference signal of the 4400 will not be used.
Input level: approx. 0 dBm
Frequency tuning range: approx. 1 ppm (10E-6) (equals 10 Hz at 10 MHz)
Input resistance: approx. 50
Ω
10 MHz OUT —
BNC socket. Output of the 4400’s internal 10 MHz reference
signal. With the help of this output, the internal time base of the 4400 can be
used to synchronize external equipment.
This output is very useful if the optional oven-controlled oscillator (OCXO) is
installed. More information on the OCXO can be found in section
Output power: approx. +5 dBm
Output resistance: approx. 50
Ω
TRIG OUT / AUX 8 —
BNC socket. Reserved for future CDMA use. Please do not
connect anything here.