In what year did they start using optical cables on the railway?

• 1985

• 1990

• 1976

• 1983

• 1993

What is the bandwidth of optical cables?

• more than 100,000 channels

• up to 480 channels

• up to 10,800 channels

• up to 16 channels

• up to 32 channels

What circuits do class I lines carry?

• main, road and operational-technology

• station

• local

• telephone

• telegraph

What circuits do class II lines carry?

• road and operational-technology

• station

• local

• telephone

• telegraph

What circuits do class III lines carry?

• local

• main

• road

• operational-technology

• station

What is the name of the electrical product consisting of one or more insulated conductors enclosed in a metallic or non-metallic sheath?

• cable

• wire

• cord

• feeder

• all answers are correct

What is the name of the product consisting of one uninsulated conductor made from one or more twisted wires enclosed in a non-metallic sheath?

• wire

• cable

• cord

• feeder

• chain

Depending on the area of application, communication cables are divided into...

• main, zone, rural, urban, wired

• underground, suspended, underwater

• low frequency and high frequency

• symmetric and coaxial

• fiber-optic

Depending on the conditions of laying and operation, cables are divided into...

• underground, suspended, underwater

• main, zone, rural, urban, wired

• low frequencies and high frequencies

• symmetric and coaxial

• fiber-optic

By the spectrum of transmitted frequencies, communication cables are divided into...

• low-frequency and high-frequency

• underground, suspended, underwater

• main, zone, rural, urban, wired

• symmetric and coaxial

• fiber-optic