COVID-19 is real and it is affecting everyone in every corner of the world. We have to protect ourselves and our loved ones from getting the coronavirus and also stop spreading the virus to others. Here are 5 essential things I think you need, at least, to have at home during the pandemic.

1. Face Masks

The face mask, either a surgical or medical mask, is essential during the COVID-19 pandemic. Face masks help slow down the spread of coronavirus. As long as you are not at home, you should wear a face mask wherever you go and change it regularly. 

I stock up some face masks (both adults and kids) especially when they are on sale. Nowadays, medical masks are widely available at online stores like Shoppee and Lazada. 

You may want to consider wearing a face shield when going to a crowded place. It is optically clear and protects the face and mask from direct splatter.

2. Hand Sanitizer and Disinfectant Spray

Hand sanitizer should be at home as well as with you while you are outside your home. Always choose a hand sanitizer containing a minimum of 60% alcohol. If you have a sensitive hand, you can get a hand sanitizer with moisturizer so it creates fewer problems for your hand.

Hand sanitizers are also available in small bottles and it is easy to carry in pocket and bag. Sanitize your hands whenever you touch a public area and there is no soap and water available.

Keep some disinfectant spays at home to clean your cellphones, car doors, bags, vegetable baskets, etc. You can use it easily to clean any surface which might be exposed. 

3. Thermometer 

A must-have item at your home even not in the coronavirus pandemic. Various types of thermometers are available out there. I think an infra-red-gun type of thermometer is the most convenient one. It measures body temperature from a distance, without contact, and thus provides safety from virus contamination via person-to-person contact.

4. Pulse Oximeter

A pulse oximeter is a small device, that you can clip on your fingertip, that uses light beams to estimate the percentage of oxygen in the blood without drawing a blood sample.

Is a pulse oximeter a necessary thing to have? I think it is recommended to have. Coronavirus cases reached a record high recently in Malaysia and some reports show that COVID-19 may cause hypoxia (a condition in which the body or a region of the body is deprived of adequate oxygen supply at the tissue level) without any symptoms and this is difficult to detect.

Keep one at home and measure regularly just in case you got COVID-19 but do not show any symptoms. COVID-19 may slowly affect your lungs and causing low blood conditions in your body.

You do not need to buy an expensive one that is used in a hospital. It’s quite cheap at the online store (mostly from China). It does not have to be very accurate because you just need to know your blood oxygen does not go below too far without any symptoms.

5. Supplements And Medicine

You need to ensure you have a good immune system during the pandemic. Stock some supplements, especially vitamins, that can help boost your immune system. Do more exercise and got more exposure to the morning sun (vitamin D).

Make sure your first aid kit contains all essential medicines such as painkillers and paracetamol (for both kids and adults). If any family member is suffering from chronic disorders like diabetes, or hypertension, make sure to stock up their medicine as well.

So, I changed the LED driver that I ordered from the China websites. It works but a month later, the same LED downlight flickered again. I changed the LED driver again and it came back working again.

Last week it became flickering again. So I decided to change the LED driver again today. This time it does not work. The LED downlight is still flickering. I measured the voltage and current of the LED driver output and they are good and stable.

So I suspect one of the LED light inside the downlight is not working properly. There are 12 LED connected in series. Since the LED is providing constant current so it is ok to short one of the LED. So I short the LED one by one to test if the downlight will stop flickering without the shorted LED in the circuit.

I was right! One of the LED was causing the problem. It was not the LED driver problem! Since I don’t have a spare LED at home, I temporary short the LED legs to prevent it from working. And my LED downlight now working perfectly good!

The LED downlight cost was about RM60. The LED is rated at 12W and it has 12 LEDs inside. So each of the LED is rated at 1W. I’m going to replace it with the 1W LED I bought from the China Website for my LED night light project, which only cost me about USD0.04 each. It wastes money if I replace the whole LED downlight with a new one :)

If the cable is still functioning, e.g. you are able to charge your phone and transfer data, do not throw it away. You can save the cable by a simple fix.

First, you need to find a heat shrink tube that is about the size of the lightning cable connector. It is better to get a heat shrink that shrink more than 50% when it is heated.

Second, cut the heat shrink tube so that it has the length enough to cover the exposed wire and the connector.

Third, apply some heat using heat gun. I don’t have a heat gun so I use a cigarette lighter. Be careful not to over heat as it will burn your cable. You can also use hair dryer.

Itâ€s a pretty easy and good looking repair. You can get heat shrink at most of the electronic shops (not the gadget shop). If you stay in KL, you can find electronic shops at Jalan Pasar at Pudu. Alternately, you can buy it online (e.g. Heat Shrink – where I bought mine).

Ok. My new gadget is in the house now – MacBook Pro with Retina Display 2015. It replaces my nearly 5 years old’s MacBook Air. My MacBook Air is still working good just that it creates a lot of heat and noise (fan) when running heavy stuffs like IDE and compiling source code.

Always want to replace one and now it is the time. MacBook Pro with Retina Display 2015 has more horse power than the Air, about the same thick & dimension of Air, better display, keyboard with back light (oh I can use it in night) but heavier.

Bought this at EpicCentre and come with some free gifts: sleeve, 8GB USB drive and a keyboard protector.

The pre-installed OS is OS X Yosemite so I need another few hours to update to OS X El Captan (which gave some performance on my old MacBook Air).

Hope this gadget will last for another 5 years before another upgrade :)

The reason for building this was, the existing LED night light that I bought from the Mr DIY is a bit dangerous because it needs to be connected to AC power source and my daughter always wants to play with it.

With this LED night light, I can connect it to any mobile phone’s power bank that has a USB port. And it is safe to play with. It doesn’t get hot even it ran for hours!

Bill of materials:

• A one watt LED (RM0.20)- bought it from the China website.
• A heat sink for LED (RM0.20)- bought it from the China website.
• A 39 ohm 1 watt resistor (RM0.10) – bought it from an electronic shop at Jalan Pasar, Pudu
• A LM317 voltage regulator (RM1.50) – bought it from an electronic shop at Jalan Pasar, Pudu
• A heat sink for LM317 (RM1.00) – bought it from an electronic shop at Jalan Pasar, Pudu
• A Mamee instant noodle cup – recycle
• A broken iPad USB cable – recycle
• Some card board – recycle

Total cost is less than RM4!

1. First, you will need to solder all the component together. You can refer to the circuit suggested in this website: http://www.instructables.com/id/Super-simple-high-power-LED-driver/

2. Make a few card boards that cut into the instant noodle cup shape. Make a hole at the middle of one of the card board and put the LED into the middle.

3. Pull other electronic components to the back. Put a layer of white paper at the side of LED for better effect. Pull back the electronic components and screw the heat sink and the LM317 together with the card board.

4. Use glue (any) to stick the card board to the instant noodle cup and it’s all done.

5. I run some test with the watt meter. It’s working at 0.9 to 1w which is within my expectation!

I can bring this light to any where because it is portable and safe. Including toilet! if I don’t want to have a very bright light at the mid night when visiting toilet.

So. What’s next? Maybe a solar panel with rechargeable battery to power this little thing? Stay tuned!

Thanks for reading!

Below is the specification of the microcontroller:

• ATmega32U4 running at 5V/16MHz
• Supported under Arduino IDE v1.0.1
• On-Board micro-USB connector for programming
• 4 x 10-bit ADC pins
• 12 x Digital I/Os (5 are PWM capable)
• Rx and Tx Hardware Serial Connections

Below is the source code for my program that emulates a card reader keyboard:

int button = 2;

void setup() {
  pinMode(button, INPUT_PULLUP); // Use internal pull up resistor
  Keyboard.begin();
}

void loop() {
  int pressed = digitalRead(button) == 0;
  if (pressed) delay(500);
  if (pressed && digitalRead(button) == 0) {
    Keyboard.println("111111");
    delay(2000);
  } else if (pressed) {
    Keyboard.println("222222");
    delay(2000);
  }
}

If you press the button once quickly, the microcontroller will send the card data string “111111” (with new line) to your PC via USB HID keyboard driver.

If you press the button once a little bit longer (around 500 milliseconds), the microcontroller will send the card data string “222222” (with new line) to your PC via USB HID keyboard driver.

I’m using a internal pull up resistor in the microcontroller itself so that I do not need to have a external resistor to pull up or down the floating digital pin (when used as input). When the input pin is pull down (when the switch is pressed) to the ground, the digitalRead will return zero value and otherwise it will be value one.

It’s so simple that you can make your program ready within minutes. Of course, you must first make sure the programming environment (IDE, the COM port of the Micro Pro is properly installed) is ready.

LINE is one of the social networking application I use frequently recently. To me, I don’t use mainly for social networking but more on connecting to the merchants that I’m interested in to find out deals and freebie :)

These are the things I have bought:

• A Raspberry Pi model B
• An Arduino starter kits
• GPIO T-Cobbler and cable
• Some Attiny85 mcu – a low power, 8 pins, AVR microprocessor

The basic idea of my home automation system is to create wireless sensor nodes that send data wirelessly to a central server. The sensors’ data will be gathered at central server, processed,  stored in database and will be presented to users via LCD display, HDMI display and website.

Sensors (like reed sensor and temperature sensor) will be connected to Attiny85 and Attiny85 will read data from the sensor and send the data to the server via radio transmitter module using radio wave. These components will form a sensor node.

Raspberry Pi (the central server) will connect to another Attiny85 which will then connect to a radio receiver module. Raspberry Pi will receive data from sensor nodes and the data will then be processed and stored in database.

Before assemble to whole home automation system, I have to test the components out so that I can make sure they can work correctly and they work as what I have expected theoretically the way they should work.

Making electronic project is fun. It takes some time to learn and it makes your hand dirty!

So, what I have done so far?

• I’m able to load the blink project into both Arduino and Attiny85.
• I’m able to make Attiny85 to talk to PC via serial communication.
• I’m able to make Attiny85 to talk to Raspberry Pi via serial communication.
• I’m able to make Raspberry Pi to display text on the LCD 1602 using I2C communication protocol.

The picture below shows the Raspberry Pi output text to the LCD display and at the same time receive data from Attiny85. It takes the whole day to program the LCD driver in Java (ported from Arduino’s LiquidDisplay driver and interface with Pi4J’s I2C library) as there is no existing driver available on the Internet.

One of the major obstacle in writing the drive is that the China’s version of LCD 1602 wires the data cable in the reverse position and it took some time to discover this! Great that it is now working correctly!

You can actually get the latest updates on-line from Astro Awani Live TV: http://english.astroawani.com/videos/live or visit the live update blog from theguardian.com: http://www.theguardian.com/world/blog/2014/mar/11/malaysia-airlines-mh370-search-refocused-on-malacca-straits-live-updates

You can also help to search the missing plane using the satellite map at http://www.tomnod.com/nod/challenge/malaysiaairsar2014. The crowdsourced effort that is being spearheaded by Digital Globe requires users to help go through 1200 square miles of ocean, and tag any suspicious objects that could lead SAR teams to the location.

You can also see what people talking about the MH370 case at twitter with hashtag #MH370 or #PrayforMH370.

Pray hard for them!

Please come back MH370, we are waiting for you!

Haze in Malaysia

The main cause of the haze is the open burning in Indonesiaâ€s Riau recently. According to the National Disaster Mitigation Agency, about 7,972ha of land and forests have been destroyed by fires in the province. The smoke fire has caused many people in the province to suffer various respiratory problems.

To monitor the haze condition, Google has recently launched a Southeast Asia (SEA) Haze Crisis Map for the public to keep an eye on the air quality levels.

Survival Guide

The haze can pose serious health hazard, especially to those with a history of respiratory illness. Other than respiratory illness, it can also affect the throat, eyes and skin. Below are some guides to survives throughout these haze-days:

Stay indoor

Stay indoor as much as possible. Stay inside your house or in a building with air-conditioned or air purifier. Do not go out for an outdoor activity. Make sure your windows and ventilation outlets at home are closed properly.

Drink more water

Drink at least 2 litres of water a day to stay hydrated. Stay away from drinks that can cause dehydration. For instance, alcohol and coffee.

Bring along instant fixes

Always make sure to have these items in your bag: face mask, eye drops, water bottle, tissue, wet wipes. These will be your instant fixes in case of red eyes, scratchy throat and trouble with breathing.

Monitor API

Keep yourself updated on the haze. Check the pollution index before you go out from your home, be it to work or to travel to other states. You can always refer to the local news paper or the Department of Environment (DOE) websites which updates on every two hours. You can also check the API on Google’s Haze Crisis Map.

Consult the doctor

Always seek for the doctor immediately if you are feeling uncomfortable, especially if you are having difficulty in breathing. Always brings your medical solutions during the haze period if you are having breathing or skin problems.

The haze problem is not something we can stop immediately, what we can do is to protect ourself and loved ones from health issues. Hope everyone can stay healthy throughout these haze-days.