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Electrical Engineering

Ethernet Switching

1. A user message is split into 15 frames, each of which has an 80% chance of arriving error-free. If no error control is used by the data link layer, how many times must the message be sent on the average to get the entire message through? 2. A communication channel has a bit rate of 14 kbps and an one-way propagation delay

Differential Amplifier Design

Please work the problem and explain how you found the necessary values. Thank you. Design a differential amplifier as shown in Figure 11.28 incorporating a basic two transistor current source to establish Iq. The bias voltages are V+=15V and V-=-15V, the transistor parameters are Beta=180 and Va=100V, and the maximum forwar

Telecommunications System

A unit for a telecommunications system is to be designed so as to have a minimum availability of 0.9994. The MTTR (mean time to repair) for the unit is estimated to be 24 hours. The unit is to consist of (n) effectively identical elements in parallel, from a reliability point of view. If the hazard rate of each of the elements i

Creating a Database with Specific Queries

Create a database with the given E-Diagram and the given queries. Emmanuel Akpan Given the schema that we decided to adopt as a standard, create the database in Oracle (or other database if you can't get Oracle to run on your machine). The data to be entered into your database is listed below. Department: Depart

Operational Amplifier

An operational amplifier (Op-Amp) circuit is built to measure the temperature of an exothermic process in a lab. The circuit uses a thermistor (Resistance Temperature Detector) to monitor the target temperature and a voltmeter to measure the output voltage of the Op-Amp ciruit. Since the thermistor is a passive device, it requ

Why can discrete-time FIR digital filters be made exactly linear phase ?

Why can discrete-time FIR digital filters be made exactly linear phase, whereas IIR digital filters cannot? I only require a sentence describing why - not any derivations of formulas etc!!!. I know what makes a filter exactly linear phase (impulse response must be symmetrical), but i don't know why IIR filters cannot be m

Comunication technology

I was wondering if you can please help me with the solution to the following questions. 1a. When a square wave with a fundamental frequency of 2khz and amplitude 5v and comprised of up to five odd harmonic (each successive odd harmonic having half the amplitude of its predecessor) is passed though a standard telephone line o

Partial fraction expansion

We have a function (see Attachment). Using a partial fraction expansion of Y(s) find Y(z) when T=0.2 seconds.

Magnetically suspended steel ball

A magnetically suspended steel ball can be described by the linear equation as shown in the attachment. The state variables are x1 = position, and x2 = velocity, and both are measurable. Select a feedback format so that the system is critically damped and the settling time (2% criterion) is 2 seconds. Solve for k1 and k2.

Full Wave Center Tap Bridge Rectifier

In the attached image, how is VDC across the load resistor found? The practice test has an answer of 28.24 ignoring the ripple voltage. VDC across the resister is Vout right? So, Vsecondary - the voltage drop in the diode = Vout = VDC So, if the secondary winding has 40voltage - .7V drop in the top resistor, that's 39.3V

Digital signal processing problem

The problem(2-61) is from the third edition of digital signal processing(proakis+manolakis) 2-61 an audio signal s(t)generated by a loud speaker is reflected at two different walls with reflection coefficients r1 and r2. the signal x(t) recorded by amicrophone close to the loud speaker, after sampling is;

Common emitter amplifer

The parameters of the transistor are Beta=100 and Va=100V. Find the DC voltages at the base and emittter terminals. See attachment for circuit.

Bias Stable Transisor Design Problem

Please help with the following problem. The DC load line and Q point of the circuit are shown next to the circuit. For the transistor, Beta=120. Find Re, R1, and R2 such that the circuit is bias stable. Is it valid for me to do a KVL around the C-E loop using ic=4.8ma and vce=6v (ie=ic (b+1/b)) to find RE? And then get

Average current and average voltage

A full-wave bridge rectifier circuit with a 1-kohms load operates from a 120-V (rms) 60-Hz household supply through a 10-to-1 step-down transformer having a single secondary winding. It uses four diodes, each of which can be modeled to have a 0.7-V drop for any current. What is the fraction of a cycle that each diode conducts? W

Signal Processing

See attachment for better symbol representation. 1. Find and sketch the spectrum of the following signal. x(t) = cos(t) + cos (2t)*cos(3t) (Express the trigonometric functions in terms of complex exponentials using one of Euler's formulae, then perform the arithmetic (multiplication) and then express x(t) in terms of sep

Finite State Machine

Finite State Machine A finite state machine (FSM) is either deterministic or non-deterministic. A deterministic FSM (DFSM) is a FSM with at most one transition for each symbol and state. A non-deterministic FSM (NDFSM) is a FSM whose transition function maps input symbols and states to a (possibly empty) set of next states. T

'Digital Filtering'- MATCAD problem

Plot the frequency response and the poles and zeroes in each case. Use a sampling frequency of one rad/sec. Compare the filter frequency responses. (See attachment for full question).

Transmission Delay

A two-port bridge connects on the end of a cable of length X m. to the end of a similar cable of length 3x/2 m. Hosts are attached at various points on the cable system, which operates as a shared-access LAN implementing the CSMA/CD protocol with a minimum frame length of 512 bits. The bridge imparts a delay in forwarding frame

IP address routing

Suppose a router has built up the routing table shown in Table below. The router can deliver packets directly over interfaces 0 and 1, or it can forward packets to routers R2, R3, or R4. Describe what the router does with a packet addressed to each of the following destinations (see Attachment)

Determine the peak-to-peak ripple current

An Rl load as shown in figure below is controlled by a chopper. If load resistance R=0.25 ohms, inductance L=20 mH, supply voltage Vs=600V, battery voltage E=150V, and chopping frequency F=250 Hz, determine the peak-to-peak ripple current (delta I). See Attached File.

RMS current ratings of a diode

The waveforms of the current flowing through a diode are shown in the figure below. Determine the RMS current ratings of the diode.

Derive the expression for the small-signal voltage gain.

The common-emitter circuit has an emitter bypass capacitor. (a) Derive the expression for the small-signal voltage gain Av(s)=Vo(s)/Vi(s). Write the expression in a form similar to that of equation (Av=(-Gm*Rpi*Rc)(Rs+rpi+(1+Beta)Re)*((1+s*taua)/(1+s*taub)). (b) What are the expressions for taua and taub? The circuit is

Diode DC Models: calculating current and diode parameters

1) Two identical diodes are connected in series with 100 ohms and a 2 V battery such that each diode is forward biased. Let Io = 10fA; n = 1, T = 25 degrees C. Calculate the loop current if (a) ideal diodes are assumed; (b) VD = 0.6 V for each diode; (c) each diode is represented by a piecewise-linear model that is exact at ID