Notes, summaries, assignments, exams, and exercises for Electronics for University

1.      18 Is it a requirement for the ARPA to provide warning on connected external equipment?

Yes

2.      Is it a requirement for an ARPA to be sea and ground stabilised?

Yes

3.      Comparing manual and automatic acquisition, which is most sensitive?

Manual acquisition

4.      What is the difference between a tracking gate and a tracking window?

It is the same thing

5.      What is the purpose of digitizing the radar echoes?

The ARPA tracking system only work with digital signals

6.      What is the purpose of the steady course filter?

Provide stabile target information

7.      Can a target reduction of speed activate the fast filter?

Yes

8.      Can a target course change deactivate the slow filter?

Yes

9.     

36.      Does current and drift effect the True vector on a relative motion display?

Yes

2.      If you input gyro course to the ARPA, what can you expect?

Error in other ships calculated course

3.      Why is raster scan display “lock up” so dangerous?

The displayed information is no longer relevant

4.      What is dangerous with operating the ARPA in mixed mode over time?

Forgetting that this actually in mixed mode

5.      What can you expect from the ARPA target tracking system in auto acquisition mode?

Small and weak targets may not be acquired

6.      Doesthe line connecting the PAD or POS whit the target indicate target speed?

No

7.      What is the meaning of a flashing triangle, apex pointing down?

New target

High

1.      What is the purpose of the HL-suppress buttom?

To switch off the HL temporarily

2.      What is the purpose of the drift control?

Used to ground stabilise true motion display

3.      What is the purpose of the brilliance control?

Adjust signal intensity on the display

4.      How to reduce beam width distortion?

Reduce gain

5.      Which course should be fed in to a stabilised radar picture?

True course

6.      What is the purpose of the VRM control?

To measure distance accurately

7.      Marine radar bearing accuracy is generally?

Not so good

8.      It is a requirement to have The HM-suppress button spring loaded?

Yes, it is an IMO requirement

9.      What is the minimum display diameter required

To control by PWM requires 2 factors:

1-crossing detection signal by 0.

2-? determine the time, every time you walk by 0.

to detect the zero crossing can be performed
through an operational amplifier connected
comparator.

TCA = 785

Pin Symbol Function

1 GND Earth

2 Q2 *Output 2 Inverted

3 Output U QU

4 Q1 * Output 1 Inverted

5 5Synchronizing voltage Vsync (to detect

zero crossing)

6 Inhibitor

7 QZ Z Output

8 8 Vref voltage stabilized (continuous signal for the

integrator)

9 9 ramp resistor R9 (for the integrator)

10 C10 ramp Capacitance (for the integrator)

11 11 V11 Control Voltage (for comparator)

12 12 C12 pulse Extension

13 LLong pulse

14 Q1 Output 1

15 Q2 Output 2

16 l sSupply voltage.

Phonetic vs. Phonological Perspectives

Looking at syllables from a phonetic point of view is different from the phonological perspective. Phonetically, syllables are described according to how they are produced and how they sound.

A syllable normally has a central part, which has little or no obstruction to the airflow and sounds louder. This central part is usually a vowel. Before and after this centre (that is, at the beginning and end of the syllable), there is more obstruction to the airflow and the sounds are usually less loud.

The Articulatory Approach

One phonetic approach tries to define syllables according to the articulatory effort needed to produce them. The psychologist R. H. Stetson suggested that syllables are related to chest pulses,...

The simple present tense

is One of several forms of present tense in English. It is used to describe habits, unchanging situations, general Truths, and fixed arrangements.

1^st Person normal, do, don’t.

3^rd Add -s question does, doesn’t,

For habits
He drinks tea at Breakfast.
She only eats fish.

Present perfect

Affirmative: 1^st have walked, 3^rd Has walked

Negative: 1^st haven’t walked, 3^rd Hasn’t walked

Interrogative 1^st have I walked? 3^rd Has she walked?

Present continuous

1^st I/you am/are going, i/you am not/ aren’t Going, am I going? Are you going?

3^rd he is going, he isn’t going, is he Going?

Present perfect continuous: Has been + ing

1^st I have been, I haven’t been, have I been living?

3^rdShe has been, she hasn't Been running, has

PRACTICE 13: TRANSFORMER SHORT-CIRCUIT TEST MEASUREMENT

Introduction

The short-circuit test involves shorting the secondary winding terminals and applying a reduced primary voltage (Ucc) to allow rated current flow in the primary winding.

Outline

Fundamentals of the Test

This test determines nominal copper losses, as short-circuit iron losses are negligible due to the low applied voltage (Ucc). Iron losses are roughly proportional to the square of the magnetic flux density (B), which is significantly reduced at low voltage. If Ucc = 5% U_1n, then Bcc ≈ 0.05B, where:

• B = maximum flux density at nominal voltage
• Bcc = maximum flux density during the short-circuit test

Therefore, P_FECCAS = (0.05)² ⋅ P_Fe = 1/400 ⋅ P_Fe, where:

• P_Fe = nominal iron losses
• P_FECCAS

Communication Technologies

*Before the advent of computers and modern technology, people communicating over long distances used traditional means such as letters and the telephone. Nowadays, we have a vast array of communication tools that can complete this task, ranging from email to instant messaging and video calls. While the present and previous means of communication are similar in their general form, they differ in regard to their speed and the range of tools available.*

Similarities in Communication Forms

One similarity between current and previous methods of communication relates to the form of communication. In the past, both written forms, such as letters, were frequently used, in addition to oral forms, such as telephone calls. Similarly,...

AC Asynchronous Motors

Direct-on-Line (DOL) Starter

(+) Simple starter scheme. High starting torque. Low cost.

(-) High starter current (input line should admit this current). Abrupt start, mechanical shock, risk of breakage. Higher bearing, belt, or chain transmission wear. Uncontrolled stopping.

(Applications) Up to 3kW motors. Small machines which can start with maximum load, without mechanical problems (bearings, belts, chains). Small water pumps, compressors, fans, and conveyor belts.

Star/Delta Starter

(+) Good torque/current ratio. Starting current reduction. Relatively inexpensive starter.

(-) Low torque at the beginning. Power failure in changing. Motor connection with 6 connectors. No velocity regulation.

(Applications) Low power fans and...