Language selection

Search

CS-03, Part VII — Requirements for Limited Distance Modems and Digital Subrate Terminal Equipment

Images

Figure 3.1.3(a): LDM Metallic 10 Hz to 4 kHz, tip and ring

Figure 3.1.3(a) describes the test circuit to verify that 2-wire limited-distance modem (LDM) terminal equipment, in the 10 Hz to 4 kHz frequency band, does not apply excessive metallic power to the network.

Back to document

Figure 3.1.3(b): LDM Metallic 10 Hz to 4 kHz, T1 & R1

Figure 3.1.3(b) describes the test circuit to verify that 4-wire limited-distance modem (LDM) terminal equipment, in the 10 Hz to 4 kHz frequency band, does not apply excessive metallic power to the network.

Back to document

Figure 3.1.3(c): LDM Metallic 4 kHz to 270 kHz, T & R

Figure 3.1.3(c) describes the test circuit to verify that 2-wire limited-distance Modem (LDM) terminal equipment, in the 4 kHz to 270 kHz frequency band, does not apply excessive metallic power to the network.

Back to document

Figure 3.1.3(d): LDM Metallic 4 kHz to 270 kHz, T1 & R1

Figure 3.1.3(d) describes the test circuit to verify that 4-wire limited-distance modem (LDM) terminal equipment, in the 4 kHz to 270 kHz frequency band, does not apply excessive metallic power to the network.

Back to document

Figure 3.1.3(e): LDM Metallic 270 kHz to 30 MHz, T & R

Figure 3.1.3(e) describes the test circuit to verify that 2-wire limited-distance modem (LDM) terminal equipment, in the 270 kHz to 30 MHz frequency band, does not apply excessive metallic power to the network.

Back to document

Figure 3.1.3(f): LDM Metallic 270 kHz to 30 MHz, T1 & R1

Figure 3.1.3(f) describes the test circuit to verify that 4-wire limited-distance modem (LDM) terminal equipment, in the 270 kHz to 30 MHz frequency band, does not apply excessive metallic power to the network.

Back to document

Figure 3.1.4(a): LDM Longitudinal Voltage 10 Hz to 4 kHz, T & R

Figure 3.1.4(a) describes the test circuit to verify that the 2-wire limited-distance modem (LDM) terminal equipment, in the 10 Hz to 4 kHz frequency band, does not apply excessive longitudinal power to the network.

Back to document

Figure 3.1.4(b): LDM Longitudinal Voltage 10 Hz to 4 kHz, T1 & R1

Figure 3.1.4(b) describes the test circuit to verify that the 4-wire limited-distance modem (LDM) terminal equipment, in the 10 Hz to 4 kHz frequency band, does not apply excessive longitudinal power to the network.

Back to document

Figure 3.1.4(c): LDM Longitudinal Voltage 4 kHz to 270 kHz, T & R

Figure 3.1.4(c) describes the test circuit to verify that the 2-wire limited-distance modem (LDM) terminal equipment, in the 4 kHz to 270 kHz frequency band, does not apply excessive longitudinal power to the network.

Back to document

Figure 3.1.4(d): LDM Longitudinal Voltage 4 kHz to 270 kHz, T1 & R1

Figure 3.1.4(d) describes the test circuit to verify that the 4-wire limited-distance modem (LDM) terminal equipment, in the 4 kHz to 270 kHz frequency band, does not apply excessive longitudinal power to the network.

Back to document

Figure 3.1.4(e): LDM Longitudinal Voltage 270 kHz to 6 MHz, T & R

Figure 3.1.4(e) describes the test circuit to verify that the 2-wire limited-distance modem (LDM) terminal equipment, in the 270 kHz to 6 MHz frequency band, does not apply excessive longitudinal power to the network.

Back to document

Figure 3.1.4(f): LDM Longitudinal Voltage 270 kHz to 6 MHz, T1 & R1

Figure 3.1.4(f) describes the test circuit to verify that the 4-wire limited-distance modem (LDM) terminal equipment, in the 270 kHz to 6 MHz frequency band, does not apply excessive longitudinal power to the network.

Back to document

Figure 3.2.1(a): Subrate Pulse Repetition Rate

Figure 3.2.1(a) describes the test circuit to verify that the terminal equipment will synchronize its output clock rate at the same data rate input on the receive tip and ring leads.

Back to document

Figure 3.2.2(a): Attenuation Weighting Curve

Figure 3.2.2(a) describes the Attenuation Weighting in dB against two frequency bands: 24 - 32 kHz band and 72 - 80 kHz band. The Attenuation Factor values in dB are given in the table provided as shown below the Figure 3.2.2(a).

Back to document

Figure 3.2.2(b): Subrate Pulse Template

Figure 3.2.2(b) describes the test circuit to verify the pulse shape of the digital signal at the output of the terminal equipment. A single positive and negative pulse are recorded, and compared to the specified criteria in the pulse mask.

Back to document

Figure 3.2.2(c): Subrate Pulse Template for 2.4 kbps

Figure 3.2.2(c) shows the subrate digital pulse mask-template for a 2.4 kbps positive isolated pulse. The amplitude values in volts corresponding to this template are given in the table as shown below the Figure 3.2.2(c).

Back to document

Figure 3.2.2(d): Subrate Pulse Template for 4.8 kbps

Figure 3.2.2(d) shows the subrate digital pulse mask-template for a 4.8 kbps positive isolated pulse. The amplitude values in volts corresponding to this template are given in the table as shown below the Figure 3.2.2(d).

Back to document

Figure 3.2.2(e): Subrate Pulse Template for 9.6 kbps

Figure 3.2.2(e) shows the subrate digital pulse mask-template for a 9.6 kbps positive isolated pulse. The amplitude values in volts corresponding to this template are given in the table as shown below the Figure 3.2.2(e).

Back to document

Figure 3.2.2(f): Subrate Pulse Template for 19.2 kbps

Figure 3.2.2(f) shows the subrate digital pulse mask-template for a 19.2 kbps positive isolated pulse. The amplitude values in volts corresponding to this template are given in the table as shown below the Figure 3.2.2(f).

Back to document

Figure 3.2.2(g): Subrate Pulse Template for 38.4 kbps

Figure 3.2.2(g) shows the subrate digital pulse mask-template for a 38.4 kbps positive isolated pulse. The amplitude values in volts corresponding to this template are given in the table as shown below the Figure 3.2.2(g).

Back to document

Figure 3.2.2(h): Subrate Pulse Template for 56 kbps

Figure 3.2.2(h) shows the subrate digital pulse mask-template for a 56 kbps positive isolated pulse. The amplitude values in volts corresponding to this template are given in the table as shown below the Figure 3.2.2(h).

Back to document

Figure 3.2.2(i): Subrate Pulse Template for 64 kbps

Figure 3.2.2(i) shows the subrate digital pulse mask-template for a 64 kbps positive isolated pulse. The amplitude values in volts corresponding to this template are given in the table as shown below the Figure 3.2.2(i).

Back to document

Figure 3.2.3: Subrate – Average Power

Figure 3.2.3 describes the test circuit to verify the total output power of the digital signal transmitted by the terminal equipment.

Back to document

Figure 3.2.4: Subrate – Encoded Analog Content

Figure 3.2.4 describes the test circuit to verify the maximum equivalent power of the encoded analog content of the transmitted digital signal.

Back to document

Formula

10log[((A2) × 56000/fbaud)/([(f/f3dB)2 + 1][(f/(fbaud × k))2 + 1])] - Additional Attenuation

Back to document

Figure 3.2.7: Subrate – Signalling Interference

Figure 3.2.7 describes the test circuit to verify that the signal power contained in the encoded analog signal in the signalling band is less than or equal to the power contained in the guardband.

Back to document

Figure 3.2.8: Subrate – On-hook Level

Figure 3.2.8 describes the test circuit to verify the equivalent analog level content in the on hook state for digital subrate terminal equipment, network protective devices and reverse battery.

Back to document

Figure 3.2.9(a): Transverse Balance Requirements

Figure 3.2.9(a) shows the transverse balance requirements for a digital TE in the range of frequencies shown in Table 3.2.7. All such TE shall have a transverse balance exceeding 60 dB for frequencies below 1000 Hz, 40 dB in the frequency range between 1000 Hz and 12000 Hz, and 35 dB in the frequency range between 12000 Hz and 64000 Hz. The longitudinal impedance for frequencies less than 12000 Hz shall be 500 ohms and for frequencies greater than 12000 shall be 90 ohms.

Back to document

Figure 3.2.9(b): Transverse Balance

Figure 3.2.9(b) describes the test circuit to determine transverse balance of digital terminal equipment.

Back to document

Figure 4.0: LDM Loop Simulator for Metallic Voltage Tests

Figure 4.0 describes the loop simulator circuits to perform the tests described in Section 3.0.

Back to document

  • RSS
  • Share
Date modified: