Cabletron Systems 42T, MICROMMAC STP Cable Specifications, Types Frequency Impedance Attenuation

REQUIREMENTS/SPECIFICATIONS

2.1.2 STP Cable Specifications

MicroMMACs 42T and 44T and TPIMs T1 and T4 support IBM Type 1, 2, 6, and 9 STP cabling as described below:

•IBM Type 1: Two STP lengths of 22 AWG solid wire for data. Used for the longest cable runs within building walls of buildings.

•IBM Type 2: Similar to Type 1 data cable, but having four additional UTP lengths of 22 AWG solid wire carried outside of the shield casing. Typically used for voice communication and often used to wire cable runs within the walls of buildings.

•IBM Type 6: 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 3/2 x Type 1 cable (66 m of Type 6 =100 meters of Type 1).

•IBM Type 9: Similar to Type 1, but uses 26 AWG solid wire. Attenuation for Type 9 cable is 3/2 x Type 1 cable (66 m of Type 9 = 100 meters of Type 1).

Attenuation and Impedance

The attenuation values shown in Table 2-3 include the attenuation of the cables, connectors, patch panels, and reflection losses due to impedance mismatches in the segment

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Table 2-3. STP Cable Specifications

Types	Frequency	Impedance	Attenuation
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.)
6 & 9	4 MHz	150Ω + 15%	<33 dB/km (10 db/1000 ft.)
	16 MHz	150Ω + 15%	<66 dB/km (20 db/1000 ft.)

Maximum Lobe Lengths

The lobe length is the physical length of the cable connecting a station to its TCU port at the MicroMMAC-T. Table 2-4 lists the maximum lobe

2-4