Why Digital Multimeter Accuracy And Precision Matter ?

Why digital multimeter accuracy and precision matter

Using a multimeter that provides the right measurements is important. Knowing what those measurements mean is even more important. Accuracy and precision ensure the measurements you take will be useful; higher precision enables easier repeatability and higher accuracy means your readings will be closer to perfect.

What is the accuracy of a digital multimeter?

Accuracy refers to the largest allowable error that occurs under specific operating conditions. It is expressed as a percentage and indicates how close the measurement displayed is to the actual (standard) value of the signal measured. Accuracy requires a comparison to an accepted industry standard.

The accuracy of a specific digital multimeter is important, depending on the application. For example, most AC power line voltages can vary ±5% or more. An example of this variation is a voltage measurement taken at a standard 115 V AC receptacle. If a digital multimeter is only used to check if a receptacle is energized, a digital multimeter with a ±3% measurement accuracy is appropriate.

Some applications, such as calibration of automotive, medical aviation or specialized industrial equipment, may require higher accuracy. A reading of 100.0 V on a digital multimeter with an accuracy of ±2% can range from 98.0 V to 102.0 V. This may be fine for some applications, but unacceptable for more sensitive electronic equipment.

Accuracy may also include a specified amount of digits (counts) added to the basic accuracy rating. For example, an accuracy of ±(2%+2) means that a reading of 100.0 V on the multimeter can be from 97.8 V to 102.2 V. Use of a digital multimeter with higher accuracy allows for a great number of applications.

Basic dc accuracy of Fluke handheld digital multimeters ranges from 0.5% to 0.025%.

How precise is a digital multimeter?

Precision refers to a digital multimeter’s ability to provide the same measurement repeatedly.

A common example used to explain precision is the arrangement of holes on a shooting-range target. This example presumes a rifle is aimed at the target’s bullseye and shot from the same position each time.


If the holes are tightly packed but outside the bullseye, the rifle (or shooter) can be considered precise but not accurate.

If the holes are tightly packed within the bullseye, the rifle is both accurate and precise. If the holes are spread randomly all over the target, it is neither accurate nor precise (nor repeatable).

In some circumstances, precision, or repeatability, is more important than accuracy. If measurements are repeatable, it’s possible to determine an error pattern and compensate for it.

What is meant by resolution in measurement?

Resolution is the smallest increment a tool can detect and display.

For a nonelectrical example, consider two rulers. One marked with 1/16-inch hatch marks offers greater resolution than one marked with quarter-inch hatch marks.

Imagine a simple test of a 1.5 V household battery. If a digital multimeter has a resolution of 1 mV on the 3 V range, it is possible to see a change of 1 mV while reading the voltage. The user could see changes as small as one one-thousandth of a volt, or 0.001 at the 3 V range.

Resolution may be listed in a meter’s specifications as maximum resolution, which is the smallest value that can be discerned on the meter’s lowest range setting.

For example, a maximum resolution of 100 mV (0.1 V) means that when the multimeter’s range is set to measure the highest possible voltage, the voltage will be displayed to the nearest tenth of a volt.

Resolution is improved by reducing the digital multimeter’s range setting as long as the measurement is within the set range.

Digital multimeter resolution detection and display

What is the range of a multimeter?

Digital multimeter range and resolution are related and are sometimes specified in a digital multimeter’s specifications.

Many multimeters offer an auto-range function that automatically selects the appropriate range for the magnitude of the measurement being made. This provides both a meaningful reading and the best resolution of a measurement.

If the measurement is higher than the set range, the multimeter will display OL (overload). The most accurate measurement is obtained at the lowest possible range setting without overloading the multimeter.

Range and Resolution

Range                     Resolution

300.0 mV               0.1 mV (0.0001 V)

3.000 V                  1 mV (0.001 V)

30.00 V                  10 mV (0.01 V)

300.0 V                  100 mV (0.1 V)

1000 V                    1000 mV (1 V)

What is the difference between counts and digits?

Digital multimeter counts and digits displayed

Counts and digits are terms used to describe a digital multimeter’s resolution. Today it is more common to classify digital multimeters by the total counts than by digits.

Counts: A digital multimeter resolution is also specified in counts. Higher counts provide better resolution for certain measurements. For example, a 1999-count multimeter cannot measure down to a tenth of a volt if measuring 200 V or more. Fluke offers 3½-digit digital multimeters with counts of up to 6000 (meaning a max of 5999 on the meter’s display) and 4½-digit meters with counts of either 20000 or 50000.

Digits: The Fluke product line includes 3½- and 4½-digit digital multimeters. A 3½-digit digital multimeter, for example, can display three full digits and a half digit. The three full digits display a number from 0 to 9. The half digit considered the most significant digit, displays a 1 or remains blank. A 4½-digit digital multimeter can display four full digits and a half, meaning it has a higher resolution than a 3½-digit meter.

source: https://www.fluke.com/en-us/learn/blog/digital-multimeters/accuracy-precision

Read More:

How to Determine Digital Multimeter Accuracy


How To Connect LED Strip Lights Together

The LED strip light is one of the multi-function lamps that both use general lighting, and are widely used in decoration, made up of LED chip technology that can light in the home. Many people believe that led strip lights are only suitable for decorative lighting, so it does not appear much in your family’s design. However, today, led strip lights are increasingly popular by improvements in designs and features from manufacturers. Because of those things, it is widely used, helping you to satisfy your passion, create new spaces.

Purchasing and installing LED lighting can be a hassle but also fun. Connecting them together sounds very complicated, but it’s also incredibly simple if you know and practices it in sequence. Now let us explore and share the problems surrounding connecting led strips with each other through this article.

Can Led Strip Lights Be Joined Together?

LED strip lights were born a long time ago – about 16 years ago, that was a great discovery of humankind. Now you can light up space with many colors such as red, orange, yellow … according to the situations and spaces you want. With one to three flashing LED string lights, you can “draw” into creative shapes such as pine trees, clouds, smiling faces or flowers, sun … on a monotonous white wall. This layout will inspire work, as well as help young children in the house, have lots of fun with interesting lights.

can led strip lights be joined together?
can led strip lights be joined together?

Can you easily connect the LED strips together? The answer is yes as long as they are the same size and use the same power supply. There are two ways to connect them: you can use the connector or solder the copper wires at the two ends to be joined together. Just use a sharp object like a knife, and pull gently to separate the outer plastic shell to reveal the inner copper joint, you can connect the strips together easily.

How Many Led Light Strips Can You Connect Together?

Talking about how many LED strips can be connected to one? Of course, it is possible and in particular:

Before connecting multiple strips of lights together, you should consider how much power is used? What is the desired length?

Using too many LED strips can cause the maximum use of the power source and the luminous power causes the circuit to heat up, so the capacity of the strip will decrease and its lifespan will also decrease.

how many led light strips can you connect together?
how many led light strips can you connect together?

Besides, on the market there are light strips that are 5 meters long, 10 meters long … You can refer to choosing the right strip of lights suitable for the space of the room you want to install.

So be careful in connecting led strips together.

A general rule of thumb if you still want to connect strip lights is to multiply the watts per meter of your strip by the length of the strip you’re powering. Then, choose a power source rated about 20% higher than that amount.

Through calculations, the MOST manufacturers recommend a maximum of 2 to 3 bands to power one PSU. However, the exact number of LED strips that you can connect to each other will always depend on the exact specifications of the equipment you have.

How Do You Connect Led Strip Lights?

In case, you have not calculated carefully or bought the wrong led strip, you still have to cut and connect the led strips together. As mentioned above, there are two main ways to connect led strips together.

how do you connect led strip lights?
how do you connect led strip lights?

The easiest way is to use a strip connector. This is how you can do it yourself at home without the help of a machine or a technician. A more complicated way is to use a weld for the connectors. It requires meticulousness and precise equipment.

#1. Use connector / clamp / cut

Self-separating the lamp cover and connecting them will be easier if using the Hippo Buckle LED strip connector. 

This connector has space for LED strip lights on each of its ends. You just need to fit the two ends of the strip into the hippo key connector to connect the two strips together. The ‘lock’ on the connector keeps the strips in position after they are installed. A hippopotamus lock can help connect two or more strips of lights together while still safe and aesthetically. 

In addition to Hippo Buckle LED strip connector, on the market, there are many other types such as Beetle Led Strip light connector, Led strip light connector, transparent connection …

#2. Solder

In case, if you are connecting the strips that will be mounted with aluminum frames, you cannot use the clamps to connect them. So you will have to solder the LED tapes together. This is not too difficult, but it does require specialized sewing and a little understanding of it.

You will need the following items: a good quality torch, wire cutters, tin wire, a clean place, a heavy object.

After preparing all the necessary tools, the power cord and the LED strip to be solder, do the following steps to solder the power cord and LED strip:

  1. Use pliers about 2-3mm wire cover.
  2. Simultaneously use the torch and tin wire on the copper core of the power cord until the tin melts. Make sure you don’t apply too much heat to get a sufficient amount of tin on the wire. Allow the weld to cool.
  3. Do the same with copper gaskets on top of the LED strip. You do this using soldering iron and tin wire at the same time, be careful not to use too much heat. A good rule of thumb is to count for 2 seconds, then stop and continue until enough. Then let them cool down.
  4. Place the end of the copper wire on the contact pad on your LED Strip. Use the torch on it and count for 2 seconds then release. Continue until the solder on it has completely melted.
  5. Hold the end of the power cord and the LED in place until it cools and adhesives.

Repeat the process with the remaining power cord until complete.

How Do You Reconnect LED Strips Without Soldering?

Before coming to the LED connection, be sure to go through the LED strip lights. Is cutting LED string simple?

As explained above, if reconnecting the LED strips without using a weld, the only way is to cut the LED strip lights and connect by the splice.

How to connect LED strip without welding details:

  1. Select the point to be cut and marked carefully. Belt connector for booting for one color. The RGB connector looks the same even though it has 4 color cables.
  2. Use scissors to cut along the marked line. Note: Cut lines will be marked on most LED Tapes with small scissor icons. You can easily find the cutoff point as it will be a straight line in between 4 solder pieces (or 8 for RGB). The cutoff points differ for LED Tape, they are every 3 LEDs for 12v and every 6 LEDs for 24v.
  3. Now take the connecting tape to the tape connector and the 2 pieces of LED tape that you want to connect.
  4. Open the connector.
  5. Slide the connector across one of your LED Tape lengths to make sure the metal pieces inside the clamp are in clear contact with the solder on the LED Tape, avoiding the remaining gap that will cause circuit loss and not close are pieced.
  6. Close the connector cover down into place, making sure that the LED tape at the right end is tight.
  7. Connect the starter connector to the transformer or extend it simply with a terminal block. The LED strip will now be active and the strip lights on.

The steps are very simple, just a little tricky.

Cutting LED strip lights is also incredibly simple. They don’t require too much skill.

However, it is important that you have the right position to cut. If the cut is not in the right position, when connecting the LED strip lights they will not light up all the LED wires. That will not only be wasteful but also cause a loss of aesthetics.

Cut the LED strip lights you need to locate.

*** Maybe you are interested: Floor Lamps For High Ceilings – Lighting the whole house space

How Do You Set Up Bluetooth Led Strips?

Smart Home is becoming a trend for modern life. The application of smart homes as popular as smartphones is only a matter of time. Right now, you can completely upgrade your living space by yourself to enjoy the amenities that technology brings.

Low-cost Bluetooth LED light controller, a short-range wireless controller that can connect directly to a smartphone or tablet without the internet. control the LED strip lights and other lights through the LED control app. Bluetooth light controller includes color management, brightness adjustment, lighting with audio input, and on and off lights. Using the Bluetooth LED light controller is also very simple. On the controller, there are text and graphic symbols that make it easier for the user to guess and use.

You can find such controllers on e-commerce sites, markets, and supermarkets for under $ 10.This is a modern product that any LED filament user knows and has. some are indoors.

How Do I Hide My LED Strip Power Supply?

Electrical safety is at the forefront with every home built. Properly installing electrical systems is also a complex issue. There are a few people who want to install more LED strips after the house is completed. So how do I hide the power supply for the LED strip?

You can forcefully choose white rectangular plastic sheets with hollow slots to conceal the wiring. It will run from the mains supply to where the strip is fixed. The power supply should be hidden to prevent the baby from touching it. By fixing it on high or obscuring it with some other decorations.

Note that the power supply should be in a dry place away from sunlight or water.

The LED strip is a long rectangular shape so cleaning is simple. You just need to clean it with a soft dry cloth and be careful to turn off the power before cleaning.

Frequently Asked Questions

How do connect the LED strips together? Sometimes there are still a few side questions so we want to synthesize and answer them for you. In this article, we will help you answer some basic questions to help you have the right view of the connected LED strip lights together. Hope it helps you.

#1. How long can LED strip lights stay on?

When buying led lights, you are often promised a very long lifespan from suppliers. So in fact, is their lifespan really that long?

A typical incandescent bulb lasts between 1,000 and 2,000 hours. But when it comes to LEDs, lamp life is often quoted from 25,000 to 50,000 hours. Long lamp life is one of the factors that makes this technology more and more popular.

Don’t confuse the life of the LED chip for the equivalent of the luminaire. Manufacturers typically only promise the life of the chip, not the entire lamp. Important accessories such as drivers often break down ahead of time. The light source (LED chip) is still working properly but will need to replace a new driver.

One thing we should know: LEDs do not “burn”. Instead, they just fade!

When a manufacturer describes their LED products as going to last 50,000 hours, it means by that time the LED chips no longer provide the required amount of light and should be replaced, not that they burn out. glow again.

The LEDs dimmed during operation. This is called lumen loss – A characteristic unique to LED technology. This process starts as soon as the light is turned on for the first time.

However, you are assured, the decrease in the brightness of the led chip is very small and usually only noticed at the end of the life commitment. Once the lamp has been illuminated for 50,000 hours, the light will be at 70% of its original rating (also known as the L70 index).

Why 70%? Actually, this number is optional. Lighting industry engineers believe that by that time, most people could feel that the brightness of the lamp really decreased and they decided to replace the lamp.

#2. How long can LED strip lights be on?

With that said, the LED lighting time can be extended up to 50,000 hours. This equates to about six years of continuous use. Over time, LEDs will slow down and lose light output and after a period of 50,000 hours, the quality of their light will drop by up to 70%.

However, there are many factors that can affect the life of the LED. The quality and durability of the materials used for manufacturing can play a part. Therefore, you need to choose reputable manufacturers because before launching the product, they have tested the LED lights through many strict stages to ensure they can work well in all different environments.

*** Read more: [Top 9 Expert Picks] Best Task Lamp For Sewing​

#3. How do you connect LED strip lights to your phone?

Absolutely and very convenient.

You can connect light strips with the Bluetooth LED light controller on your phone through apps available on AppStore (IOS), Google Play (androids) …

Access the “LED Controller” search bar. Find the appropriate application and click download to use it.

How to use smart LED strip lights in general for applications

Step 1: Download the app you wish to use (example: LampUX)

Android users on Google Play and iOS can go to the App Store and download the App to their phone, then register for an account.

Step 2: Set up the smart LED strip

Turn on the LED strip lights and wait for 10 seconds. Then, press and hold the power button on the remote for more than 5 seconds. The light will flash at a frequency of 2 times per second.

Step 3: Connect the application

Open the App and after registering and logging in you will see the button “+” in the upper right corner. Click it and find the LED strip light you want to add and select the “Confirm quick blinking indicator” to see the prompt for Wi-Fi connection. Enter your Wi-Fi username and password to connect. After a few seconds, your LED strip will be added to the App and you can modify the name for better identification, then save it. With these simple steps, you can control your smart LED strip through the Mobile App.

The above steps are default EZ mode to connect the lights to the App. Alternatively, you can connect via AP mode.

#4. What happens when you cut LED Strip Lights?

When you cut a strip of LED, the strip of lights will be immediately separated, causing the metal connection circuits to open. If not promptly handled (reconnect them), someone activates the power source, causing an open circuit when touching may be jerky, even death. When reconnecting the wrong circuit, the strip will not light up because the current cannot be passed through.

The strip lights are cut very easily, but care should be taken that they do not cause unexpected accidents.

With the knowledge and experience that we share above, we hope it will help you in connecting LED strips. Whichever way you choose, you should get to know it well and do it as safely as possible. Connect, use them to make your home more vivid.

Read more:

7 Ways How to dry boots in dryer?

how to dry boots in dryer

While work boots are built to withstand a beating, they require constant maintenance and repair to maintain their protective characteristics. This is especially true if you operate in a damp area.

If wet boots are not correctly handled, they can cause a slew of problems. While many males believe that letting their boots air dry overnight would suffice, they are frequently startled to find that their boots are still dripping wet in the morning.

While work boots are built to withstand a beating
While work boots are built to withstand a beating

Who wants to go around in dripping wet boots all day? It is not only unpleasant, but it may have an impact on your entire job effectiveness and safety. Wet boots can promote the growth of germs, emit unpleasant smells, and cause painful blisters.

Don’t be concerned if you find yourself in the perilous scenario of needing to dry your work boots before your next shift. There are several simple and efficient ways for quickly drawing out moisture.

Before you start

#1. Start the process asap

As soon as you return from your trek, begin the process of drying your shoes to allow optimum drying time throughout the evening.

#2. Clean them first

Clean them first
Clean them first

All traces of mud should be eliminated before beginning to dry your shoes. This is due to the fact that leaving dirt on the boots when drying them may result in a permanent discoloration on the surface. For more details, see our blog on How to Clean Suede Walking Shoes, which offers helpful tips on how to clean them.

#3. Remove the insole if possible

If the insoles of your shoes can be removed, do so whenever feasible. This allows each insole to dry independently and more effectively. Furthermore, by removing the insoles, air can travel throughout the shoes and reach the hidden away sections, allowing the entire boot to dry more quickly. This feature should be available in many high-quality walking boots.

*** Read More: Top Expert Choice The Best Skechers Zumba Shoes 2021 

#4. Take out the laces

This may appear to be a bother, but removing the laces ensures that your boots dry quickly. Laces, like insoles, will be able to dry more successfully independently, and air will be more likely to reach portions of the shoes that the laces normally hide.

#5. Avoid direct heat

avoid direct heat
Avoid direct heat

The best and safest approach is to dry your boots without exposing them to direct heat. Of course, a heater, wood burner, or bonfire may be required to assist expand the overall size of the room or space, but boots should not be placed immediately in front of or near them. This is mostly due to the fact that excessive heat can harm the exterior of the boots, such as glue or other components that keep the shoes together. Using a blow dryer is also discouraged.

How to dry boots in the dryer?

Using a Boot Dryer

This is a great device for anyone who has a number of pairs of walking boots or shoes. A decent drier should have about two horsepower to guarantee that there is enough hot air to adequately dry the shoes. Simply insert the pipe into the boot and press it all the way to the toe edge. Then, turn on the dryer. Allow one to two hours for a totally dry boot.

5 Other ways to dry your wet boots

Depending on the resources at your disposal, you may dry your boots overnight in a variety of methods.

#1. Using Newspaper or Kitchen Roll

If you have any of these materials on hand, filling your boots with them is an excellent way to absorb extra moisture. The best approach to load your boots with newspaper is to remove sheets and wrap them up into tiny balls. The rolls should be relatively loose, as water may not be absorbed efficiently if they are too tight.

Another method is to make holes in the newspaper before scrunching it. Place the paper or kitchen roll all the way up into the leg opening of the boot. Again, don’t stuff it too tightly since the paper needs some breathing room to soak up the water. Replace the kitchen roll or newspaper after a few hours to eliminate the first load of moisture before sleeping, or as needed after the materials have been saturated.

#2. Using Rice

To utilize either of the above materials, you will also need a bucket of the appropriate size to set your boots in, along with the rice. Fill the bucket with rice until it is about an inch high, then place the shoes inside. Insert the socks and cover the top with a lid before leaving it overnight. Similarly, to the newspaper approach, you can change the rice wherever you see fit, depending on how much moisture you want to eliminate.

#3. Using a Fan or Cat Litter in a sock

This is widely considered as one of the most effective and secure techniques of drying walking shoes overnight. The ideal method is to use a non-heated fan with a long stand. To connect the boots to the fan, you’ll need a cable that can hook onto the fan’s exterior and the shoes. Place a cloth beneath the boots to absorb any water droplets while they dry. It is best to leave the fan running overnight if possible. You may also dry your shoes using cat litter in a sock-like you would with rice.

#4. Using a Towel

The towel technique is similar to the newspaper approach, except that a towel is used to absorb up the wet. Make sure you clean the shoes first and then stuff two towel corners inside each boot. Then, wrap the towel’s remaining two sides around the shoes to completely cover them. The towel should be removed after a few minutes to absorb the first wetness. Leave and repeat the process with a new, dry towel. It is preferable to use old towels for this approach, as you might expect!

#5. Using Power of the Sun

Why not make use of the sun, which is free, natural, and effective? Simply place your boots outdoors in an area that receives direct sunlight.

The sun’s beams evaporate moisture and destroy germs that promote bacterial development.

The primary disadvantage of sun drying is the amount of time it takes. It is not the quickest solution. Not only that, but you’re subject to Mother Nature’s whims. It is advised that you do not rely on this approach all of the time.

If your boots are not properly maintained, excessive sun exposure might eventually harm the leather substance.

#6. Put them in a Dry Room

This is critical to ensuring that all of your hard work does not go to waste! Taking the time to dry your boots using any of the techniques listed above and then placing them in a chilly, wet room can result in soggy shoes. Make sure the area or location where you keep them overnight is dry and warm.

*** See Now: Top 5 Best Zumba Shoes For Bad Knee 

What You Shouldn’t Do

One thing to keep in mind is that all of these approaches require time. When it comes to preserving your boots, speed is of the essence. A rather slow drying procedure will aid in the prevention of damage.

While it may be tempting, it is critical that you do not utilize direct heat to speed up the process. Using blow dryers, stoves, ovens, or heaters is one example of this.

The leather uppers will be permanently damaged if exposed to direct heat. Excessive heat will cause the fabric to wrinkle and break. Furthermore, the heat might have an effect on the adhesive that keeps your boots together.

Having said that, there are occasions when applying a little heat is your only option. For example, you may be working in a distant place with just a bonfire to keep you warm.

If this is the case, keep your boots at least 2 to 3 meters away from the flames. The boots will be able to benefit from the heat without being damaged.

Is Will putting shoes in the dryer damage the dryer?

Dryers are reasonably sturdy, but they, like your shoes, maybe damaged when heavy objects are placed in them. The easiest method to avoid injury is to follow the advice above, particularly the one about dangling shoes from the door.

You should never put loose shoes in the dryer. When free shoes are placed inside the machine, the frequent tumbles and pounding might cause internal damage. It may also wreak havoc on your kicks.

You may, however, use towels or even clothing to cushion them. It’s a good idea to put them in a wash bag with a couple of towels. This will function as cushioning, reducing harm.

However, the best way to prevent damaging your shoes and machine is to simply avoid using them.


Nothing beats a rejuvenating walk in the midst of nature’s splendor. Walking, rain or shine has several physical and emotional advantages. However, knowing that you would have to put on damp shoes the next day in order to continue the trip is quite unappealing! We’ve put up a guide to help you dry your boots overnight so you can tackle the trails in comfort and ease the next day. Hope this post is useful for you!

Contact with Florsheimxesquivel Review:

Refer Article

  • https://www.lowa.co.uk/lovelowa/86-how-to-dry-your-boots-overnight

Buzzed Buzzer – Buzzes only when you’re drunk!

How to make your own Buzzed Buzzer

  • Alcohol sensing party buzzer
  • Buzzed Schematic


  • New Years’ party horn (get a few in case you ruin one – they’re cheap)
  • Teensy 2.0 microcontroller (anything similarly tiny like the Arduino Micro should also work)
    • Hint use this pinout reference page for the Teensy
  • Alcohol sensor
  • 10kohm resistor
  • Any buzzer that works on about 5v – we used this one
  • Sparkfun LiPo battery and charger
  • 0.1” male header pins
  • wire
  • blu-tac
  • The Buzzed Buzzer Arduino sketch


  • Soldering iron, solder, solder wick (or a solder sucker)
  • Angled wire cutters
  • Needle nosed pliers
  • Wire strippers
  • Computer with Arduino IDE and Teensyduino installed


Part 1: Set up the Alcohol Sensor

  1. The alcohol sensor has two sets of three pins – solder one set together with a bit of wire – this is now the positive side of the sensor.
  2. Solder a red wire to the positive side.
  3. Look at the pins with the positive side to your right, solder the 10k resistor between the two lower left pins.
  4. The middle left pin is now ground and the upper left pin is the signal pin.
  5. Solder a brown wire to the ground pin and a blue wire to the signal pin.
  6. Before use, the alcohol sensor needs to be burned in for 24 hours. Solder the sensor’s ground and positive leads to the GND and VCC pins on the Teensy, and plug the Teensy into a powered USB hub or phone charger for 24 hours.

Part 2: Wire the Circuit Together

  1. Solder the Alcohol sensor’s signal line into pin 22 of the Teensy (or any analog input pin if you’re using a different microcontroller)
  2. Solder the buzzer’s black wire to the Teensy’s GND pin
  3. Solder the buzzer’s red wire to pin 10 on the Teensy
    • Any other digital output pin except for TX should work if you’re using a different microcontroller
  4. Break off two male header pins and solder a pair of wires to them.
  5. Solder the black wire to the Teensy’s GND pin
  6. Solder the white wire to the Teensy’s VCC pin
  7. Now you can plug the LiPo battery into the Teensy to provide it with power – just make sure you plug it in black to black.
    • Note don’t ever have both the battery and the computer plugged into the Teensy at the same time – bad things could happen.
  8. Download the Arduino code from the Simple Switch Labs’ Git repository and open it with the Arduino IDE and load it onto the Teensy.
  9. Test your circuit by wafting some alcohol near the alcohol circuit – the buzzer should start and stop pretty quickly when you bring alcohol near and remove it again, but it won’t be perfect.

Part 3: The Horn

  1. Gently remove the plastic nozzle from the party horn then use your needle nosed pliers to remove the thin plastic reed from inside the horn.  If you blow through the nozzle, it should no longer make any noise.
  2. Flatten the horn so it’s no longer perfectly round, you want it to be a bit oval – this will allow air to pass the alcohol sensor when someone tries to blow in it.
  3. Replace the nozzle onto the horn.
  4. Gently start inserting the circuit into the horn, sensor first, a little bit of Blu-Tac is helpful for keeping things stuck where they should be
    • Note use some Blu-Tac to help ensure there is plenty of room for air to bypass the sensor – you don’t want to seal up the horn
  5. Plug the battery in and give your horn a test.

How it works:

Not via any kind of blood alcohol measurement.

Because the alcohol sensor isn’t the most accurate sensor in the world, all the code really does is look for the presence of alcohol – if it sees a nice spike, it sounds the alarm.  So you can just swish something in your mouth and it will still work. You can always modify the code so the buzzer needs to see a lot more alcohol to sound the alarm.

If you’re curious or just want to experiment, you can see the data from the alcohol sensor by leaving it plugged into your computer and using the serial monitor on the Arduino IDE (it sends at 9600 bps).


Created at Havas Chi by Tyler DeAngelo & Sacha De’Angeli. Fabricated at Simple Switch Labs