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The tele-printer signal “Who are 0177 7660 വാ ೦೩118 80080710078 06160717867 18 ೩ :
(ക) Proceed - to - select signal (B) Calling signal
(C) Call connceted signal (D)’ Clearing signal

The term PSTN stands for :
(A) Public Switched Telex Network (B) Public Switched Telecom Network
(C) ‘Private Switched Telex Network (D) Private Switched Telecom Network

The supervisory signal indicates the Free-line condition (the normal condition of a
disengaged circuit) in telex service is :

(ಗ) Positive potential on each transmission path

(B) Negative potential on each transmission path

(C) Positive potential on the forward-signalling path
(D) Negative potential on the forward-signalling path

The Crossbar telephone exchanges come under the category വ്‌:
(ക) Mechanical switching systems (B) Electromechanical switching systems
(C) Analog switching systems (D) Digital switching systems

The printed indication of service signal “OCC” in telex கொண்க represents :
(ಗಿ) Spare outlet reached ८ (8) Subscriber’s line engaged:
© Trunks or equipment engaged (D) None of the above

The printed service signal for ‘Subscriber’s line out of service’ condition in telex service is :
ക NC (B) NP
(C) ABS (D) DER
Five unit code was used in teleprinter systems. The maximum number of combinations that
can be obtained from 5-unit code is :
@) 32 ®) 64
(0 128 D) 256

Which of the following is not true with respect to 5- unit code used for teleprinter working?
(ക) The number of characters obtainable is sufficient for teleprinter purposes
(B) The transmission time is different for different characters
(C) All characters are composed of same number of signal elements

(D) All the signals consist of combination of two electrical conditions

102/2015 12 ட