TELEPHONE INTERFACE MODULE (TIM)

14.11.6 FINAL PATH INSPECTION

If all of the mechanical assembly has been made properly, the connections in Table 14-11should exist.

Table 14-11 E&M TO TERMSETCONNECTIONSSLOT 1
6132/Backplane [1]J3 [2]E&M DB-15 [3]

 

 

 

 

 

Pin #

Signal

Pin #

Signal

Pin #

 

 

 

 

 

41

Tx Tip

26

Rx +

1

47

Tx Ring

1

Rx Gnd

6

7

Rx Tip

27

Tx +

8

13

Rx Ring

2

Tx Gnd

10

21

M-Lead

29

E-Lead

13

23

E-Lead

28

M-Lead

14

 

 

SLOT 2

 

 

 

 

 

6132/Backplane [1]

J3[2]

E&M DB-15 [3]

 

 

 

 

 

Pin #

Signal

Pin #

Signal

Pin #

 

 

 

 

 

41

Tx Tip

30

Rx +

1

47

Tx Ring

5

Rx Gnd

6

7

Rx Tip

31

Tx +

8

13

Rx Ring

6

Tx Gnd

10

21

M-Lead

33

E-Lead

13

23

E-Lead

32

M-Lead

14

[1]Information from Page 10 of 6132 handout, corresponds to page 5 of rack handout.

[2]Information from Page 4 (Table 3) of rack handout.

[3]Information from E&M card schematics.

14.12 BACKGROUND INFORMATION

14.12.1 STANDARD SIGNAL

The standard signal is defined as a 1 kHz audio tone modulated to ±2 kHz deviation, with data modulated to ±1 kHz (total deviation is ±3 kHz).

14.12.2 OUTLINED OBJECTIVE

The specific technical purposes of tuning the repeater and 4-Wire E&M are to ensure:

1.The RF hardware is properly tuned.

2.Data levels (LTR and high speed) are properly set, both in/out of the Radio Concentrator.

3.In dispatch mode, Audio In = Audio out of the repeater.

4.Levels transmitted to and received from the CO are given adequate gain.

5.The hybrids interfacing system equipment to the CO are properly balanced.

6.The links all have unit gain across them.

7.Interconnect and Dispatch audio are at the same level (in terms of Exciter deviation).

The purpose of tuning the Switch is to ensure all audio coming into the Switch, either from an RF channel, a Telco resource, or a Network Link, bus at the same level. In other words, regardless of where audio originates, the amplitude is the same level in the Switch. Once achieved, the Switch directs the audio in from any resource out to any other resource with all the proper levels.

Standard audio received from a mobile is defined in terms of ±2 kHz of audio deviation (±3 kHz total). Defining standard audio from the Central Office (CO) is not as simple. It ranges from -10 to -30 dBm, depending on distance from the CO and line quality. One objective of the tuning procedure is to determine the level of average audio from the CO, and to normalize that level.

Tuning the system ensures that ±2 kHz of audio received from a mobile results in the same level on the backplane as does the CO standard level.

Once the levels are properly set, ±2 kHz of audio deviation is injected into the receiver and

±2 kHz of audio deviation is transmitted from the Exciter (dispatch). Also, standard audio coming in from the CO results in ±2 kHz of audio deviation transmitted from the Exciter (interconnect). Finally, ±2 kHz of audio deviation injected into the Receiver results in a standard audio level transmitted to the CO.

14.12.3 THE ORDER OF THINGS

First, properly tune the RF equipment. Next, the repeater (dispatch) channels. ±2 kHz of audio in, gives

±2 kHz of audio out.

14-27