MEDIA SPECIFICATIONS AND REQUIREMENTS
B.2 SHIELDED TWISTED PAIR (STP)
STP cable categories are listed as follows:
•IBM Type 1 consists of two STP lengths of 22 AWG solid wire for data. There are three versions of Type 1: Indoor, Outdoor, and Plenum. It is typically used for the longest cable runs within the walls of buildings.
•IBM Type 2 is similar to Type 1 data cable, but has four additional UTP lengths of 22 AWG solid wire carried outside of the shield casing. There are two versions of Type 2: Plenum and Outdoor. It is typically used for voice communication and often used to wire cable runs within the walls of buildings.
•IBM Type 6 consists of two STP lengths of 26 AWG stranded wire for data. Used in patch panels or to connect devices to/from wall jacks. Attenuation for Type 6 cable is 150% of Type 1 cable (e.g., 66 m of Type 6 =100 meters of Type 1).
•IBM Type 9 is similar to Type 1, but uses 26 AWG solid wire. Attenuation for Type 9 cable is 150% of Type 1 cable (e.g., 66 m of Type 9 = 100 meters of Type 1).
Impedance and Attentuation
The attenuation values shown Table
Table B-2. STP Cable Specifications
Type | Freq. | Impedance | Attenuation |
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1 & 2 | 4 MHz | 150Ω + 15% | <22 dB/km (6.7 db/1000 ft.) |
| 16 MHz | 150Ω + 15% | <45 dB/km (13.7 db/1000 ft.) |
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6 & 9 | 4 MHz | 150Ω + 15% | <33 dB/km (10 db/1000 ft.) |
| 16 MHz | 150Ω + 15% | <66 dB/km (20 db/1000 ft.) |
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