Notes, abstracts, papers, exams and problems of Electronics

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Classified in Electronics

Written at on English with a size of 6.04 KB.


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

... Continue reading "Radar" »


Classified in Electronics

Written at on English with a size of 4.31 KB.

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


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


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?


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



... Continue reading "Arpa" »


Classified in Electronics

Written at on English with a size of 4.64 KB.


1.      How does radar antenna height influence on sea clutter

High antenna height more sea clutter

2.      The horizontal extension of the target affects the echo pulse?


3.      The reflection of radar pulses is similar to that of?


4.      What is the relation between scanner width (size) and horizontal beam with?

Large scanner with, narrow horizontal beam width

5.      What are the two main purposes of marine radar?

Traffic surveillance and navigation

6.      What is the function of the magnetron?

Generate radar pulses

7.      Does the ships trim affect radar minimum range?


8.      What is the main function of the receiver?

Amplify the incoming signals

9.      Does the number of pulses transmitted

... Continue reading "Radar" »


Classified in Electronics

Written at on English with a size of 4.56 KB.



1.      A ship aspect mean?

Target ship bearing of own ship

2.      How can you detect a dangerous target on a relative motion display?

The target is closing in with no bearing change

3.      How does the WO line represent in the plotting triangle?

Own ships course

4.      What does the WA line represent in the plotting triangle?

Targets course

5.      What is ARPA?

Computerised radar plotting device?

6.      What is the most used Graphical presentation of target speed and course on an ARPA?

Relative or true speed vectors

7.      What does manual acquisition mean?

The operator must select and acquire each target manually

8.      What is the requirement for ARPA detection?

Performance not inferior to the radar

... Continue reading "Arpa" »

USB module configuration in the PIC 18F4550

Posted by Javi and classified in Electronics

Written at on English with a size of 34.96 KB.


"Transfer Rate: It can be low speed (1.5 Mb / s) or high speed (12Mb / s).

- Sop orta Interrupts. Every time there is a transmission or reception of data on the bus, it generates an interrupt to the PIC to the routine care which must respond by managing all aspects of low level of the USB specification. Thus for the main application running on microcontroller USB protocol handling is transparent.

-Allows use of up to 32 EndPoints (16-way) but usually only use 3 (Endpoint 0, 1 and 2). An endpoint is a buffer that stores data within the device (typically a record). In turn, each endpoint has a unique identifier that is assigned to a particular factory and data flow direction (IN / OUT). All devices must support endpoint 0, which is... Continue reading "USB module configuration in the PIC 18F4550" »


Classified in Electronics

Written at on English with a size of 3.97 KB.

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


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?


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

New target

... Continue reading "Arpa" »


Classified in Electronics

Written at on English with a size of 4.66 KB.

1.      36 What is the effect of using incorrect bearings in plotting?

CPA, TCPA, Course and Speed are affected

2.      What is the main purpose of Seaspeak?

Reduce maritime communication problems

3.      What is the effect of error in time between two plots?

Error in CPA, TCPA and target course

4.      What is the usual method of deciding whether collision danger exists or not?

By talking several bearings of the target


5.      What is the main purpose of plotting?

Obtain information about whether danger of collision exists, CPA, TCPA, target course and speed

6.      What is the effect of gyro error?

All bearings will be wrong

7.      Radar navigation have X important motion components?


8.      Use of radar to assist

... Continue reading "Radar" »

Power control.

Classified in Electronics

Written at on English with a size of 40.96 KB.

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


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
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.
2Q ==

Programmable Logic Controllers

Classified in Electronics

Written at on English with a size of 11.78 KB.

The term PLC widely available in the middle means in English, Programmable Logic Controller. It was originally called PCs (Programmable Controllers), but with the arrival of the IBM PC, to avoid confusion, we used the acronym PLC definitively. In Europe, the same concept is called PLC. The more appropriate definition is: Industrial System Automatic Control working under a sequence stored in memory, logic instructions. It is a system because it contains everything needed to operate, and industrial by having all the records necessary to operate in the harsh environments found in industry

Historical Presentation PLC's

was first introduced in 1960 in the industry about the need to eliminate the large outlay which was produced by replacing the

... Continue reading "Programmable Logic Controllers" »

Exercicis reported speech

Classified in Electronics

Written at on English with a size of 3.95 KB.


A few = Unos Pocos

Quite few = Muy pocos

Few = Pocos

Very few = Muy pocos

A little = Un poco

Little = Pequeño

Very Little = Muy poco

No = No

None = Ninguno

Not any = No cualquier

A lot of = Un montón de

Lots of =  Un montón de

Quite a lot of =  Bastante de

A great deal of =  Una gran Cantidad de

A large number of =  Un gran Número de

A large Amount of =  Una gran cantidad de

Every = Cada

Each = Cada

Whole = Todo

All = Todas

Any = Alguna

Most of = La mayoría

Passive Voice

Reported Speech

Modals + Be + 3ra 






Have to





Must=Had to


This= That




Today=That Day

Tonight=That Night

Tomorrow=The Next

Yesterday=The Day Before

This Evening=That Evening

Last Week=The week Before