Engineering Answers

An electronic device is available that will reduce this year’s labor costs by Php10,000. The equipment is expected to last for eight years. If labor costs increase at an average rate of 7% per year and the interest rate is 12% per year. a. What is the maximum amount that we could justify spending for the device? b. What is the uniform annual equivalent value of labor costs over the eight-year period?

A firm considering the installation of an automatic data processing unit to handle some of its accounting operations. Machines for that purpose may be purchased for Php200,000 or maybe leased for Php80,000 for the first year and Php10,000 less every year now and then until the end of the 4th year. If money is worth 15%, is it advisable to rent or buy the machine? 

The maintenance on a machine is expected to be Php15,500 at the end of the first year and it is expected to increase by Php3,500 each year for the following 7 years. What sum of money should be set aside now to pay the maintenance for the eight year period? Assume 6% interest.

Represent the binary data stream 10110101 in a given line coding format:

(i) Bipolar NRZ (ii) Polar RZ (iii) AMI (iv) Split Phase

How does an integrate and dump receiver maximize the signal to noise ratio?

How is it different from a correlation receiver? Draw the diagrams, wave forms

and mathematically show the analysis.

Draw and Explain the transmitter and receiver of BFSK. Draw the signal space

representation of it.

Compare integrate and dump receiver and matched filter ? Analyze the goal

of a matched filter? Draw the diagrams, wave forms and mathematically

show the analysis.

Describe the significance of DSBSC signal in terms of its expression, waveform and

power efficiency. Also discuss in which condition an envelop detector be used to

demodulate a DSBSC signal or and in which condition not.

Two signals a(t)=10cos(100Πt) and b(t)=15cos(5000Πt) are applied to a non-linear

device to generate an AM signal with output y(t)= 3 + 2v + 4v^2. Find expression of

the AM signal, calculate its modulation index, bandwidth and draw its spectral

response. Also draw the circuit with required parameters which will be able to

produce this AM signal.

A signal is given by the expression y(t) = 10 cos(200 pi t) + cos^2(100 pi t).cos(300 pi t) + 5

Represent the signal in frequency domain and calculate its bandwidth.