RCDD TEST 2025 QUESTIONS| WITH
ALREADY SOLVED CORRECTLY
ANSWERS!! | ASSURED SUCCESS
If the input signal power to a communication system is 1 W and the output
power is 1 mW, the system attenuation is:
A. 3 dB
B. 20 dB
C. 30 dB
D. 40 dB
E. 1000 dB - 🧠 ANSWER ✔✔C. 30 dB
The signal at the input to a balanced twisted pair cable is 10 mW. The
cable is 1000 feet long and has an attenuation of 1 dB per 100 feet. This
cable is connected to the input of a receiver. The noise level at the input to
the receiver is 1 microwatt. What is the signal-to- noise ratio (SNR) (dB) at
the receiver input?
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,A. 10 dB
B. 30 dB
C. 40 dB
D. 60 dB
E. 100 dB - 🧠 ANSWER ✔✔B. 30 dB
A SONET OC-1 channel can carry 672 voice signals and has a data rate of
51.84 Mbps. ASONET OC-48 channel can carry 32,256 voice channels.
What MINIMUM data rate is required for the OC-48 channel?
A. 155 Mbps
B. 622 Mbps
C. 2.5 Gbps
D. 5 Gbps
E. 10 Gbps - 🧠 ANSWER ✔✔C. 2.5 Gbps
All of the following are nominal wavelengths for laser light sources
EXCEPT:
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STATEMENT. ALL RIGHTS RESERVED
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,A. 700 nm
B. 850 nm
C. 1300 nm
D. 1310 nm
E. 1550 nm - 🧠 ANSWER ✔✔A. 700 nm
A video camera has a coaxial cable output. The video signal is to be
distributed to devices that have balanced twisted pair inputs. The transition
between these two different transmission media can be accomplished by
using a:
A. Balun
B. Converter
C. Modulator
D. Cross connect
E. Transceiver - 🧠 ANSWER ✔✔A. Balun
The public telephone system is an example of a __________ system.
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STATEMENT. ALL RIGHTS RESERVED
3
, A. Simplex
B. Half-duplex
C. Full-duplex
D. Purely analog
E. Purely digital - 🧠 ANSWER ✔✔C. Full-duplex
Wave division multiplexing (WDM) is most similar to:
A. Amplitude modulation
B. Frequency modulation
C. Time division multiplexing
D. Frequency division multiplexing
E. Carrier sense multiple access with collision detection (CSMA/CD) - 🧠
ANSWER ✔✔D. Frequency division multiplexing
You must place CAT6 cable above a factory floor with automated welding
machines and hammer forges. Of the following, what type of shielding
would be most effective?
COPYRIGHT©NINJANERD 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
4
ALREADY SOLVED CORRECTLY
ANSWERS!! | ASSURED SUCCESS
If the input signal power to a communication system is 1 W and the output
power is 1 mW, the system attenuation is:
A. 3 dB
B. 20 dB
C. 30 dB
D. 40 dB
E. 1000 dB - 🧠 ANSWER ✔✔C. 30 dB
The signal at the input to a balanced twisted pair cable is 10 mW. The
cable is 1000 feet long and has an attenuation of 1 dB per 100 feet. This
cable is connected to the input of a receiver. The noise level at the input to
the receiver is 1 microwatt. What is the signal-to- noise ratio (SNR) (dB) at
the receiver input?
COPYRIGHT©NINJANERD 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
1
,A. 10 dB
B. 30 dB
C. 40 dB
D. 60 dB
E. 100 dB - 🧠 ANSWER ✔✔B. 30 dB
A SONET OC-1 channel can carry 672 voice signals and has a data rate of
51.84 Mbps. ASONET OC-48 channel can carry 32,256 voice channels.
What MINIMUM data rate is required for the OC-48 channel?
A. 155 Mbps
B. 622 Mbps
C. 2.5 Gbps
D. 5 Gbps
E. 10 Gbps - 🧠 ANSWER ✔✔C. 2.5 Gbps
All of the following are nominal wavelengths for laser light sources
EXCEPT:
COPYRIGHT©NINJANERD 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
2
,A. 700 nm
B. 850 nm
C. 1300 nm
D. 1310 nm
E. 1550 nm - 🧠 ANSWER ✔✔A. 700 nm
A video camera has a coaxial cable output. The video signal is to be
distributed to devices that have balanced twisted pair inputs. The transition
between these two different transmission media can be accomplished by
using a:
A. Balun
B. Converter
C. Modulator
D. Cross connect
E. Transceiver - 🧠 ANSWER ✔✔A. Balun
The public telephone system is an example of a __________ system.
COPYRIGHT©NINJANERD 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
3
, A. Simplex
B. Half-duplex
C. Full-duplex
D. Purely analog
E. Purely digital - 🧠 ANSWER ✔✔C. Full-duplex
Wave division multiplexing (WDM) is most similar to:
A. Amplitude modulation
B. Frequency modulation
C. Time division multiplexing
D. Frequency division multiplexing
E. Carrier sense multiple access with collision detection (CSMA/CD) - 🧠
ANSWER ✔✔D. Frequency division multiplexing
You must place CAT6 cable above a factory floor with automated welding
machines and hammer forges. Of the following, what type of shielding
would be most effective?
COPYRIGHT©NINJANERD 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
4
