Mad Of Electronics

Here u can find some useful tips and links related to troubleshooting electronic appliances
Showing posts with label kattankulathur. Show all posts
Showing posts with label kattankulathur. Show all posts

WASHING MACHINE WATER DRAIN PROBLEM

Posted by rajascientist Monday, August 17, 2009 0 comments

Recently I came across a washing machine ,the problem was it was not draining the water after spinning. It was an Whirlpool automatic washing machine. I opened the back cover gained access to the drain hose .

Actually draining of water will be actuated by pulling the piston out.It is done by a motor gear assembly ,which pulls the string connected to the drain hose. I pulled the string manually water gushed out immediately. So the problem might be with that drain motor or with the swith which actuates this motor.


After removing the machine completely I found that the small motor gear set has been rusted by water.Some how water has entered and it spoiled everything. I took that motor set and opened its cover.

Inside it was a permanent magnet AC motor ,which runs on 220V 50Hz supply. I carefully removed all the gears and gained access to the motor. I removed that motor and connected it to 220V ,but the motor struggled to spin.

So i found out the problem , It was this faulty motor. Actually rust has developed around the stator which prevented free rotation of the motor. I cleaned and removed the rust, now again the motor spins perfectly.

I carefully assembled the gears back to its position and screwed it to the machine. Now it works perfectly. If still the problem exists , better replace the drain motor.

SOME FAQs ABOUT SWINE FLU

Posted by rajascientist Saturday, August 15, 2009 0 comments

What is the best way to keep from spreading the virus through coughing or sneezing?

If you are sick limit your contact with other people as much as possible.Do not go to work stay at home or in your hotel room.Cover your mouth and nose with a mask when coughing or sneezing.It may prevent those around you from getting sick.Put your used tissue in the waste basket.If you do not have a mask cover your cough or sneeze whenever you cough or sneeze.Then clean your hands every time you cough or sneeze.

For what purposes can antiviral drugs be used against influenza A(H1N1)?

So far most people who have contracted the new A (H1N1) virus have experienced influenza-like symptoms (such as sore throat, cough, runny nose, fever, malaise, headache, joint/muscle pain) and recovered without antiviral treatment. Antiviral drugs may reduce the symptoms and duration of illness, just as they do for seasonal influenza. They also may contribute to preventing severe disease and death. Influenza A (H1N1) is a new virus and only a small number of people with the infection have been treated for it with antiviral drugs. WHO is in touch with public health authorities and clinicians in affected countries and is gathering information about how effective the drugs are.

Is there a human vaccine to protect from Swine Influenza ?

There are no vaccines that contain the current swine influenza virus causing illness in humans.It is not known whether current human seasonal influenza vaccines can provide any protection.Influenza virus changes very quickly.This is why WHO needs access to as many viruses as possible in order to select the most appropriate candidate vaccine virus.

To which antiviral drugs does this influenza virus respond?

There are two classes of antiviral drugs for influenza: inhibitors of neuraminidase such as oseltamivir and zanamivir; and adamantanes, such as amantadine and rimantadine. Tests on viruses obtained from patients in Mexico and the United States have indicated that current new H1N1 viruses are sensitive to neuraminidase inhibitors, but that the viruses are resistant to the other class, the adamantanes. Could the virus become resistant to oseltamivir and zanamivir? Resistance can develop to antiviral drugs used for influenza. Therefore, WHO and its partners are monitoring antiviral drug resistance.

Under what circumstances should antiviral drugs be administered?

Antiviral drugs are to be used according to national pandemic influenza preparedness plans. Public health authorities in some countries have decided to treat patients likely to have this disease as a part of public health measures. Where antiviral drugs are available for treatment, clinicians should make decisions based on assessment of the individual patient's risk. Risks versus benefits should also be evaluated on a case by case basis.

Should I take an antiviral now just in case I catch the new virus?

No. You should only take an antiviral, such as oseltamivir or zanamivir, if your health care provider advises you to do so. Individuals should not buy medicines to prevent or fight this new influenza without a prescription, and they should exercise caution in buying antivirals over the internet.

What is WHO doing about getting antiviral drugs to countries as preparation for a pandemic?

WHO’s first priority is to provide an emergency stock of antiviral drugs to countries that have no or insufficient stock of the drugs and lack the capacity to procure these drugs themselves. WHO is also working with Member States, donors and other groups that have stockpiles and are willing to share these with WHO for distribution to countries in need.

Which drug will be provided, and how much of it does WHO have available?

WHO had a global stockpile of approximately 5 million adult treatment courses of oseltamivir. Part of this stockpile has already been distributed through the WHO Regional Offices, which are handling allocation and distribution. WHO is currently distributing the remaining 3 million adult treatment courses of this stockpile to developing countries in need. WHO continues to assess needs and to work with manufacturers to secure more donations of antivirals. More antiviral drugs will be distributed once these donations are received.

DANGEROUS SWINE FLU

Posted by rajascientist Thursday, August 13, 2009 1 comments

WHAT IS SWINE FLU?

Swine Influenza ( swine flu) is a respiratory disease of pigs caused by type A influenza viruses (H1N1 subtype) that causes regular outbreaks in pigs. People do not normally get swine flu ,but human infections can and do happen.

Swine flu viruses have been reported to spread from person to person, but in the past ,this transmission was limited and not sustained beyond three people.

SIGNS AND SYMPTOMS

The symptoms of swine flu in people are similar to the symptoms of regular human flu and include

  1. Fever
  2. Sore throat
  3. Cough
  4. Body ache
  5. Head ache
  6. Fatigue
  7. Chills
Some people have reported diarrhea ad vomiting associated with swine flu.

In the past several illness ( pneumonia and respiratory failure)and death have been reported with swine flu infection in people.

Like seasonal flu swine flu may cause a worsening of underlying chronic medical conditions.

HOW DOES SWINE FLU SPREAD?


Spread of this swine influenza A (H1N1) virus is thought to be happening in the same way that seasonal flu spreads. Flu viruses mainly spread from person to person through coughing or sneezing of people with influenza. Some times people may get infected by touching something
with flu virus on it and then touching their mouth or nose.

WHAT SHOULD I DO IF I GET INFECTED?

In children emergency warning signs that needs urgent medical attentions include:

  • Fast breathing or trouble in breathing
  • Bluish skin color
  • Not drinking enough fluids
  • Not waking up or not interacting
  • Being so irritable that child does not want to be held
  • Flu-like symptoms improve but then return with fever and worse cough
  • Fever with a rash

In adults emergency warning signs that needs urgent medical attentions include:

  • Difficulty breathing or shortness of breath
  • Pain or pressure in the chest or abdomen
  • Sudden dizziness
  • Confusion
  • Severe or persistent vomiting

AUDIO AMP FROM JUNK CD PLAYER

Posted by rajascientist Wednesday, August 12, 2009 25 comments

Many junk electronics gadgets can be used to get some useful spare parts and some times amplifier circuit,transmitter,receiver etc.,


I got a junk CD player a few weeks back i opened it and took some useful things some motors,laser diode, IR receiver, and finally a Dual channel Audio amplifier.



The IC was CD6283CS and its specifications are as follows


4.6 W x 2 dual-channel audio power amplifier

Model: CD6283CS

Product Name: Dual-channel audio power amplifier
Overview and Application: CD6283CS is one pair of channel audio power amplifier can be used in portable and hand-made audio power amplification


Features:
1). Large output power

2). Boot "sound of escaping laughter" small voice
3). Quiescent current small

4). Soft clamp function

5). Built-in overheating protection circuit
6). Wide range of supply voltage: VCC = 6V to 15V Package: FSIP12


I took that amplifier circuit and assembled it in another small case ( i used a junk fish tank motor).


I just drilled four holes to accompany two volume control , one Bass and One Treble. Now i fitted the main amplifier board and took out all the connecting wires.














Now I got a handy audio amplifier which i can use it for my hobby projects.

PERSEIDS METEOR SHOWER

Posted by rajascientist 0 comments

The Perseids are a prolific meteor shower associated with the comet Swift-Tuttle. The Perseids are so called because the point they appear to come from, called the radiant, lies in the constellation Perseus.

Meteor showers occur when Earth moves through a meteor stream. The stream in this case is called the Perseid cloud and it stretches along the orbit of the Comet Swift-Tuttle. The cloud consists of particles ejected by the comet as it passed by the Sun.




Most of the dust in the cloud today is approximately a thousand years old. However, there is also a relatively young filament of dust in the stream that was pulled off the comet in 1862.


The rate of meteors originating from this filament is much higher than for the older part of the stream. The Perseid meteor shower has been observed for about 2000 years, with the first known information on this meteor shower coming from the Far East. In early medieval Europe, the Perseids came to be known as the "tears of St. Lawrence."

The shower is visible from mid-July each year, with the greatest activity between August 8 and 14, peaking about August 12. During the peak, the rate of meteors reaches 60 or more per hour.

They can be seen all across the sky, but because of the path of Swift-Tuttle's orbit, Perseids are primarily visible in the northern hemisphere.




Year
Perseids active between
Peak of shower
2009
14 July - ...[1]
Expected: 11 August - 12 August [2]
2008
25 July - 24 August [3]
13 August (ZHRmax 116) [3]
2007
19 July - 25 August [4]
13 August (ZHRmax 93) [5]
1972

12 August: reported to be the most active shower in recorded history

SYSTEM SHUTDOWN DUE TO THERMAL HEATING

Posted by rajascientist Sunday, August 9, 2009 1 comments

This was the message I got few months ago whenever I started my PC , sometimes suddenly my PC will go off and When I restart again the same message appeared.

I thought I would have over used my Computer but thats not the problem I know, because system can be used continuously throughout the day .

I removed the cooling fan and heat sink placed directly above the processor and cleaned it.

Fan was working good, heat sink was cleaned and now its free from dust. I cleaned the heat sink with cycle pump. Now assembled everything back in to its position . Again I got the same message .

This time I removed CPU fan , heat sink also the processor beneath.

It was difficult to remove the processor, the heat sink compound was dried and it was difficult to remove the processor.

Heat sink compound is a white paste like substance applied over the processor and at the bottom of the heat sink. It is mainly used for cooling and can be obtained at local shop.

I bought a new compound and applied it . But when started my PC it ran good for a while again it stopped, showing the same message.

Now I removed all the wire connections from SMPS and checked the wires . Finally I found the culprit.

It was a four pin from the SMPS yellow, black wire i.e, 12v wire. The wire end was blackened.I opened the SMPS and rectified the fault now My system is working fine.

WATER OVER FLOW PROBLEM IN WASHING MACHINE

Posted by rajascientist Saturday, August 8, 2009 0 comments



Troubleshooting Whirlpool Auto sparkle Washing Machine :


The problem with the washing machine was over flowing of water . It has a water level controller with options namely Extra low, low, Medium , High and reset.



High water level is selected for washing more clothes , that is when the tub is full .
But the problem is whenever the water level is selected to High , the starts filling even after the level is reached and it over flows.

This is mainly due to the faulty water level controller shown above or the tube which connects the controller and the water tub. The water inside the tub creates a pressure depending upon the level of water present in the tub .This pressure controls the water level controller .

I resolved this problem by loosening the screw in the water level controller , thereby making it easy to stop water over flowing. The more you loose the screw less the water pressure is required to stop water intake.

SOME MORE VICTIMS OF LIGHTNING

Posted by rajascientist Friday, August 7, 2009 0 comments



In my previous post I shared my experience about my UPS now I have two more devices to share with you all. One thing is Electronic Choke and the other Emergency lamp.


Electronic Fluorescent lamp choke:

I got a tube light with no response ,from one of my customer .His doubt was lightning. I opened the electronic choke and his doubt was right it was affected by lightning. I just had a look at the PCB, line to a small transformer inside was burnt .


I just gave a parallel connection to it using a small bit of wire. I checked each and every component inside and everything works fine. After connecting the choke I switched on and the tube light glows.

Emergency lamp:

Another case was with an emergency lamp which is plugged in while charging and was affected by lightning .



The green light was not glowing that is battery is not charging but it can discharge . The lamp glows with the residue charge present in the battery.

After opening the lamp having a look at the PCB found a hole in the PCB , might have got a severe volt. Fortunately everything was fine I checked each and every component . Now as usual I traced the line and gave a parallel line to the small transformer whose circuit was burnt.


Now i plugged in and switched on the lamp ,the green light glows and the battery is charging . Every thing works fine.

LIGHTNING AFFECTED GADGETS

Posted by rajascientist 0 comments

Like many other guys me too very much interested towards electronics and I like troubleshooting them. Here I am going to share some of my experience regarding electronic gadgets affected by lightning .

Normally a device gets affected by lightning when its power chord is just plugged in , doesn't matter its switched on or not, just a plugged chord is enough to get affected by lightning.


First thing I am going to share is about my UPS

UPS:

One night I left my UPS plugged in , but power is switched off . I went to sleep , around midnight I heard a loud bang like how a glass piece dropped down will make shattering sound. I woke up and ran towards my PC and TV thought one of my picture tube would have burst. Luckily both was safe , I happily went to sleep without knowing the whats waiting for me the next day , next morning when I switched on my PC, UPS has no response and at that time I recalled what happened last night.




Opened my UPS, removed PCB board , what I saw was along the border of PCB the ground line was burnt and lost two diodes, which I found later after testing with Multimeter.

I just tracked down the line of PCB and just soldered a piece of wire instead of that line and replaced those diodes. Now it works fine .


I have seen some more devices affected by lightning .In my experience ,when compared to other faults lightning causes PCB burning normally it doesn't spoils any components.

HUNGER FACTS

Posted by rajascientist Tuesday, August 4, 2009 0 comments

Give free food with one click. Visit http://www.bhookh.com/




1.
Hunger remains the No.1 cause of death in the world. Aids, Cancer etc. follow.

2.
There are 820 million chronically hungry people in the world.

3.
1/3rd of the world’s hungry live in India.

4.
836 million Indians survive on less than Rs. 20 (less than half-a-dollar) a day.

5.
Over 20 crore Indians will sleep hungry tonight.

6.
10 million people die every year of chronic hunger and hunger-related diseases. Only eight percent are the victims of hunger caused by high-profile earthquakes, floods, droughts and wars.

7.
India has 212 million undernourished people – only marginally below the 215 million estimated for 1990–92.

8.
99% of the 1000 Adivasi households from 40 villages in the two states, who comprised the total sample, experienced chronic hunger (unable to get two square meals, or at least one square meal and one poor/partial meal, on even one day in the week prior to the survey). Almost as many (24.1 per cent) had lived in conditions of semi-starvation during the previous month.

9.
Over 7000 Indians die of hunger every day.

10.
Over 25 lakh Indians die of hunger every year.

11.
Despite substantial improvement in health since independence and a growth rate of 8 percent in recent years, under-nutrition remains a silent emergency in India, with almost 50 percent of Indian children underweight and more than 70 percent of the women and children with serious nutritional deficiencies as anemia.

12.
The 1998 – 99 Indian survey shows 57 percent of the children aged 0 – 3 years to be either severely or moderately stunted and/or underweight.

13.
During 2006 – 2007, malnutrition contributed to seven million Indian children dying, nearly two million before the age of one.

14.
30% of newborn are of low birth weight, 56% of married women are anaemic and 79% of children age 6-35 months are anaemic.

15.
The number of hungry people in India is always more than the number of people below official poverty line (while around 37% of rural households were below the poverty line in 1993-94, 80% of households suffered under nutrition).

Sources :

UN World Food Programme
UN World Health Organization: Global Database on Child Growth and Malnutrition, 2006
UN Food and Agriculture Organization: SOFI 2006 Report
National Commission for Enterprises in the Unorganized Sector (India)
National Family Health Survey 2005 – 06 (NFHS-3) (India)
Centre for Environment and Food Security (India)
Rural 21 (India)

HUMAN AS A BATTERY

Posted by rajascientist Monday, August 3, 2009 0 comments

Electrical impulses in the heart originate in the sinoatrial node and travel through the intrinsic conducting system to the heart muscle.The impulses stimulate the myocardial muscle fibres to contract and thus induce systole. The electrical waves can be measured at selectively placed electrodes (electrical contacts) on the skin.


These small electrical signals can be measured using a multimeter. Adjusting the multimeter to 200 or 2000mv dc the electrical signal produced can be measured. The strength of this signal vary from point to point ,that can be understood by touching multimeter electrode at different places on our skin.

When i measured my own body signals i got around 125 mv sometimes, suddenly i an idea flashed me i thought of amplifying this voltage to produce around 1 volt so that i can light some small bulb.

So now how to amplify , thought for a while then one thing struk my mind thats the voltage multiplier .


A voltage multiplier is an electrical circuit that converts AC electrical power from a lower voltage to a higher DC voltage by means of capacitors and diodes combined into a network. Voltage multipliers can be used to generate bias voltages of a few volts or tens of volts or millions of volts for purposes such as high-energy physics experiments and lightning safety testing.


The above circuit is an example of typical voltage quadrupler a type of voltage multiplier,



I used around 10 capacitors and diodes that is output volt is 10 times the input voltage. The circuit is in process I will tell u later whether I succeeded in lighting a small bulb.


PUBLIC GRIEVANCES

Posted by rajascientist Sunday, August 2, 2009 0 comments

Government of India has an online Grievance forum at http://www.pgportal.gov.in

Can you imagine this is happening in INDIA ?

The govt. wants people to use this tool to highlight the problems they faced while dealing with Government officials or departments like

11) National Saving Scheme of Ministry of Finance
19) Central Universities
20) ESI Hospitals and Dispensaries directly controlled by ESI Corporation under Ministry of Labour

Many of us say that these things don't work in India .
Couple of months back, the Faridabad Municipal Corporation laid new roads in his area and the residents were very happy about it. But 2 weeks later, BSNL dug up the newly laid roads to install new cables which annoyed all the residents.. A resident used the above listed grievance forum to highlight his concern.. To his surprise, BSNL and Municipal Corporation of Faridabad were served a show cause notice and the guy received a copy of the notice in one week. Government has asked the MC and BSNL about the goof up as it's clear that both the government departments were not in sync at all.

So use this grievance forum and educate others who don't know about this facility.
This way we can at least raise our concerns instead of just talking about the 'System' in India .

CRYSTAL RADIO

Posted by rajascientist 0 comments

A crystal radio is the distilled essence of a radio. It has very few parts, it needs no batteries or other power source, and it can be built in a short time out of things you can find around the house.






The reason a crystal radio does not need any batteries is the amazing capabilities of the human ear. The ear is extremely sensitive to very faint sounds. The crystal radio uses only the energy of the radio waves sent by radio transmitters. These radio transmitters send out enormous amounts of energy (tens of thousands of watts). However, because they are usually far away, and we have at most a few hundred feet of wire for an antenna, the amount of energy we receive with the crystal radio is measured in billionths of a watt. The human ear can detect sounds that are less than a millionth of even that.


The above circuit shows a simple crystal radio. U can also add some capacitors to the above circuit, a capacitor in series with the antenna coil allows high frequency to pass through enabling better performance and reception.




Instead of ear phone u can also use a telephone receiver to listen to channels.

Eye Safety During Solar Eclipses

Posted by rajascientist Wednesday, July 22, 2009 0 comments

The Sun can be viewed safely with the naked eye only during the few brief seconds or minutes of a total solar eclipse. Partial eclipses, annular eclipses, and the partial phases of total eclipses are never safe to watch without taking special precautions. Even when 99% of the Sun's surface is obscured during the partial phases of a total eclipse, the remaining photospheric crescent is intensely bright and cannot be viewed safely without eye protection [Chou, 1981; Marsh, 1982]. Do not attempt to observe the partial or annular phases of any eclipse with the naked eye. Failure to use appropriate filtration may result in permanent eye damage or blindness!



















Generally, the same equipment, techniques and precautions used to observe the Sun outside of eclipse are required for annular eclipses and the partial phases of total eclipses [Reynolds & Sweetsir, 1995; Pasachoff & Covington, 1993; Pasachoff & Menzel, 1992; Sherrod, 1981]. The safest and most inexpensive of these methods is by projection, in which a pinhole or small opening is used to cast the image of the Sun on a screen placed a half-meter or more beyond the opening. Projected images of the Sun may even be seen on the ground in the small openings created by interlacing fingers, or in the dappled sunlight beneath a leafy tree. Binoculars can also be used to project a magnified image of the Sun on a white card, but you must avoid the temptation of using these instruments for direct viewing.
The Sun can be viewed directly only when using filters specifically designed for this purpose. Such filters usually have a thin layer of aluminum, chromium or silver deposited on their surfaces that attenuates ultraviolet, visible, and infrared energy. One of the most widely available filters for safe solar viewing is a number 14 welder's glass, available through welding supply outlets. More recently, aluminized mylar has become a popular, inexpensive alternative. Mylar can easily be cut with scissors and adapted to any kind of box or viewing device. A number of sources for solar filters are listed below. No filter is safe to use with any optical device (i.e. - telescope, binoculars, etc.) unless it has been specifically designed for that purpose. Experienced amateur and professional astronomers may also use one or two layers of completely exposed and fully developed black-and-white film, provided the film contains a silver emulsion. Since all developed color films lack silver, they are always unsafe for use in solar viewing.
Unsafe filters include color film, some non-silver black and white film, medical x-ray films with images on them, smoked glass, photographic neutral density filters and polarizing filters. Solar filters designed to thread into eyepieces which are often sold with inexpensive telescopes are also dangerous. They should not be used for viewing the Sun at any time since they often crack from overheating. Do not experiment with other filters unless you are certain that they are safe. Damage to the eyes comes predominantly from invisible infrared wavelengths. The fact that the Sun appears dark in a filter or that you feel no discomfort does not guarantee that your eyes are safe. Avoid all unnecessary risks. Your local planetarium or amateur astronomy club is a good source for additional information.
In spite of these precautions, the total phase of an eclipse can and should be viewed without any filters whatsoever. The naked eye view of totality is completely safe and is overwhelmingly awe-inspiring!

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