Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Q. What do you mean by Dial Pulses?
Dial Pulses: Dial pulsing (many times known as rotary dial pulsing) is the method originally used to transfer digits from a telephone set to local switch. Pulsing digits from a rotary switch began soon after invention of the automatic switching machines. The idea of dial pulsing is quite simple and is depicted in figure. Process begins when telephone set is lifted off hook, completing a path for current through local loop. When switching machine detects off-hook condition, it responds with dial tone. After hearing the dial tone, subscriber begins dial pulsing digits by rotating a mechanical dialling mechanism and then letting it returns to its rest position. As rotary switch returns to its rest position, it outputs a series of dial pulses corresponding to digit dialled.
Whenever a digit is dialled, loop circuit alternately opens (breaks) and closes (makes) a prescribed number of times. Number of switch make/break sequences corresponds to digit dialled (that is the digit 3 produces three switch openings and three switch closers).
Dial pulses take place at 10 make/break cycles per second (which is a period of 100 ms per pulse cycle). For illustration digit 5 corresponds to five make/break cycles lasting a total of 500ms. Switching machine senses and counts the number make/break pairs in sequence.
Break time is nominally 61 ms and make time is nominally 39ms. Digits are separated by idle period of 300 ms called inter digit time. It is important that switching machine recognize the inter digit time so that it can separate pulses from successive digits. Central office switch incorporates a special timeout circuit to ensure that break part of dialling pulse isn't misinterpreted as phone being returned to its on-hook (idle) condition.
Q. What is the need of MODEM in data communication? Need of Modem: Modems are used to interface computers, computer networks in addition to other terminal equipment to teleco
A 3 phase 60 hertz induction motor has 8 poles and operates with a slip of .05 for a certain load. Compute in r.p.m. the (a)speed of the rotor with respect to the stator, (b)spe
what is that mean and explain
A Capacitor-Fed, Voltage-Step-Down, Single-Phase, Non-Isolated Rectifier
Q. With the help of a npn transistor circuit and wave forms explain the working of an astable multivibrator In astable multivibrator both transistors are coupled to each other
A 20µF capacitor is connected in series with a 50 kΩ resistor and the circuit is connected to a 20 V, d.c. supply. Verify: a) The initial value of the current flowing, b) T
Demodulators for FM Figure shows a block diagram of a general FM demodulator, which is implemented by generating an AM signal whose amplitude is proportional to the instantane
simplified common base hybrid model
transistor biasing stabilization problems
Distinguish between ferromagnetic and paramagnetic materials, mentioning at least one example of each. Ferromagnetic Materials: These are materials wherein magnetic dipoles i
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd