User's Manual

Table Of Contents

22 Using the CTU with a TB8100 TBA0STU/TBA0STP CTU Operation Manual

IOIOI

This is an RS-232 serial port. Connect it to a PC running the Service Kit

or Calibration Kit software when calibrating or tuning the base station. You

must also connect a system control bus cable between the CTU (via

connector

2#) and the reciter for this interface to work.

POWER The POWER LED is lit when the CTU is powered up. You can supply

power to the CTU in the following ways (see Figure 4.3 on page 26):

■ connect power directly using the DC input socket 2@

■ let the reciter provide power over the system control bus connector 2#

■ let the reciter’s system interface provide power over the system interface

connector

1!. This requires that you connect power to the reciter’s

auxiliary DC input connector adjacent to the system interface.

You can safely connect power to two or more of these connectors at the

same time.

Note You do not need to provide power to the CTU at all in order to

make audio level measurements or to use the digital inputs and

outputs. Lack of power will not affect these interfaces.

Important Do not power the CTU from a PMU fitted with a 48V

auxiliary power supply board. The maximum supply volt-

age for the CTU is 32VDC. Use either a PMU 12VDC or

24VDC auxiliary output, or an external power supply.

Note that the auxiliary output can be supplied to the CTU

via the system interface connector on the reciter if the aux-

iliary DC power cable is fitted, as well as via a direct con-

nection to the PMU auxiliary output.

NOISE The CTU’s internal, wide bandwidth noise source is available on this

output. You can connect the NOISE socket to the RF input on the reciter

and use it to tune the receiver’s front end. The adjacent switch turns the

noise on and off. The bandwidth of the noise source is approximately

50MHz to 1GHz, and the output level is approximately –130dBm/Hz.

This output level is equivalent to –91dBm typical for a narrow bandwidth

receiver, –89dBm typical for mid bandwidth, and –88dBm typical for wide

bandwidth.

LINE INPUT The CTU makes audio at this input available to the TB8100 transmitter (it

connects LINE INPUT to the balanced line input on the system interface

connectors).

UNBALANCED/OFF/

BALANCED

This switch directs either the balanced or unbalanced receiver output audio

to the CTU speaker. When set to “OFF”, no audio is present on the

speaker.