IBM 1PA, Operational, Installation, And Maintenance Manual

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DB25 cables must meet or exceed the electrical characteristics in Table 6-3.
Table 6-3. Requirements for DB25 Cables
8-Pair shielded wire gage 26 (7x34)
Characteristic impedance 110
±
10 ohm @ 1
MHz
DC resistance 42.6 ohm/1000'
Capacitance between conductors 18 PF/1' @ 1 MHz
Capacitance conductor to shield 31 PF/1' @ 1 MHz
Attenuation 30 dB/1000' @ 1
Mhz
Fiber Optic Conventions and Standards
The multiplexer uses LED transmitters operating at a wavelength of 820
nanometers and PIN photodiodes as receivers.
Important: The optical transmitter contains an LED system and is classified
“CLASS 1 LED PRODUCT” per EN60825-1 (+A11),
Safety of Laser Products.
Should the unit ever require maintenance, contact an authorized service location for
repair.
Use the fiber interface with 62.5/125 um diameter graded index multimode duplex
fiber with ST type terminators, as shown in Figure 6-4.
BOOT
BAYONET STYLE
COUPLING NUT
FERRULE
HUB1I044
Figure 6-4. Fiber Optic Terminator
Chapter 6. Cables and Baluns
6-5