AN93

V.90 modems must be tested with a digital modem, such as the USR Courier I. If a digital modem isn’t used as illustrated in Figure 47, the highest connection speed a V.90 modem will support is 33.6 kbps. A call can be placed or received in either direction at the speed set in the modems. A test script must be written for a computer to control the dialing, monitor the call progress, send a file, and compare the received and sent files. Figure 47 illustrates this test configuration.

Teltone ILS 2000

ISDN

ISDN Modem

 

ISDN

ISDN

Terminal

Adaptor

Test

Computer

Analog

Modem Under Test

Figure 47. V.90 Modem Functional Test Connection

Table 151 compares the coverage of &T2, &T3, and full bidirectional functional testing.

Table 151. Test Coverage

Circuit or Function

&T2

&T3

Functional Test

 

 

 

 

Si24xx chip

Yes

Yes

Yes

 

 

 

 

ISOcap Operation

Yes

Yes

Yes

 

 

 

 

Si3018/10 Operation

 

Yes

Yes

 

 

 

 

Hookswitch

 

Yes

Yes

 

 

 

 

dc Termination

 

Yes

Yes

 

 

 

 

Bridge

 

Yes

Yes

 

 

 

 

AC Termination

 

Yes

Yes

 

 

 

 

Line Voltage Monitor

 

 

Yes

 

 

 

 

Ringer Network

 

 

Yes

 

 

 

 

Intrusion Detection

 

 

Yes

 

 

 

 

Caller ID

 

 

Yes

 

 

 

 

Overcurrent Detection

 

 

Yes

 

 

 

 

Rev. 1.3

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Silicon Laboratories SI2494/39, SI2493/57/34/15/04 manual Teltone ILS, Isdn Modem, Modem Under Test, Test Coverage