simplest off delay timer

-
Hello, I will show you how to make an off-timer delay.
This circuit is simple and uses only 3 electronic components.
The off time of this circuit is around 15 seconds.
But you can change the R-value to increase or decrease off time.
Let's make it like the below video.

Comments

Post a Comment

Popular posts from this blog

Resistor color code

-
Image
A resistor is the most important electrical component in almost every electronic circuit, it can limit current to any load such as led, transistor, op-amp, etc.  We must read the resistor color code if we want to know the resistive value, tolerance, temperature coefficient. Resistors have different color bands (3,4,5,6) the more color bands the more resistor information. Now let's start with 3 bands resistor color code. The above resistor has only 3 bands First digit, Second digit, and multiply. A 3 bands resistor color code has a fixed +/- 20% tolerance which means if the color code value is 1,000 ohms the real-life resistive value may be +/- 200 ohms.  4 band resistor color code A 4 bands resistor color code has a tolerance value color strip, the resistor on the above picture has 5% tolerance. This type of resistor uses in a regular circuit such as television, radio, washing machine. 5 bands resistor color code A 5 bands resistor colo...
Read more

How to add power supply filter capacitor to amplifier board.

-
Image
I saw a new comment on my video, he asked me how to add a filter capacitor to amplifier board D.C. power supply. I think it's a good question so I will explain it here. What is a power supply filter capacitor? It is the capacitor that used to filter AC ripple from DC power supply present to amplifier board. If an amplifier has low capacitive power supply capacitor, it may present a little hum(50/60 Hz low-frequency sound) that you can hear in a quiet room. The capacitor also stores power and bring it instantly to your amplifier when an amplifier needs more power for a short period of time such as  explosion sound in a movie. However, If an amplifier has high-frequency power supply noise from a switching power supply, small capacitor need to parallel to a power supply and must be attached close to power amplifier IC as much as possible. Below pictures are the place that you add power supply capacitor. PAM 8610 board amplifier powe...
Read more

How to connect volume control to an amplifier

-
Image
I saw a comment on my Youtube video, he asked me how to connect any amplifier module to a volume control or potentiometer. I think so many people who want to start an electronic project must know this basic wiring too, I hope this wiring diagram will help an electronic DIYer like me. First thing you need to know: use shield wire for an input signal to volume control and from volume control to amplifier if you don't want you amplifier suffers from parasitic oscillation (sound like JeeeeJeeeee). keep a wiring as short as possible. use low resistive value volume control (5-10 kilo-ohms) if the amplifier has random parasitic noise when you turn a volume control up or down. volume control is a potentiometer. Volume control principle is a signal divider, the more volume control output(yellow line) near input signal source(pink line) the most signal flow to an amplifier. When you lower a volume control the resistive va...
Read more

Hall effect sensor wiring diagram and test video

-
Image
Hall effect sensor switch is a switch that turns on when enough magnetic field near the IC. You can use hall effect sensor to make many Diy projects such as rpm meter, magnet detector, and more project involves with a magnet. Did you know? Hall effect sensor uses in many electric machines, example; when you open washing machine door and the machine stop spinning, or when you open microwave door then it pauses and send beeping sound until you close the door. Hall effect sensor IC in this post is A3144(old component but work well and low cost) Send output low (0 volts) when strong magnetic field near a sensor, that why somebody asked on the internet why his project involves hall effect sensor didn't work. Hall effect sensor wiring diagram. You can see an above image that a load(LED in this picture) connect to positive electrode and output instead output and ground. That's the reason why some projects don't work and will never work because the output low when magn...
Read more

simple bass booster circuit diagram

-
Image
This bass boost diagram is easy to build and work well, I made it because people asked me the schematic diagram of bass boost diagram on my youtube channel. The circuit has 9 dB gain@40 Hz that mean you will get good bass performance even you play music to a small speaker. Why this circuit doesn't look like circuits on the internet? Almost every circuit on the internet uses R/C filter between pre-amp and power amp stage to bypass high frequency to a ground and that seems audio signal being amplified and bypass to ground. I think it wastes pre-amplifier gain, the more gain preamp stage the more distortion to the audio signal, so I use a capacitor to send more negative feedback to pre-amp negative input when the frequency higher than cut-off frequency, capacitor impedance(resistance) higher when frequency lower and that make negative feedback decrease when frequency lower. An op-amp distortion lowers when negative feedback higher, that mean high-frequency disto...
Read more

5 watts amplifier TDA7056A wiring diagram

-
Image
TDA 7056 A is an audio power amplifier IC that has 5 watts output power with 8 ohms speaker and 3 watts with 16 ohms speaker. The IC is simple to wiring and needs only 6 external components to make the amplifier working. TDA 7056A working with a power supply between 4.5 - 18 volts so the IC can use a battery as power supply. if you use more than 9 volts, you need to attach small heat sink to the IC. TDA7056A has a built-in DC volume control so you can control the gain of the amplifier by changing voltage value at DC volume control pin by use a potentiometer. DC volume control makes you connect the audio signal directly to the amplifier input so it makes a sound more transparent and cleaner than a normal amplifier.  The IC has a short circuit protection, over temperature protection, No switch-on/off clicks, ESD protected on all pins, Mute mode (The IC switch mode when DC volume control pin voltage lower than 0.3 volts)  TDA 7056A has a very wide audio bandwidth 20 H...
Read more

how to make condenser microphone pre-amplifier

-
Image
I saw a comment on my youtube video that he want to connect condenser microphone directly to pam8610 amplifier board. However, if he needs to connect condenser microphone to any amplifier board he must bias and amplify the signal before. Now let's start!!! Condenser microphone need a power supply to bias circuit inside that why we need specific preamplifier for it. You need two electronic component to make condenser microphone to operate  1. 2 to 10 kilo-ohms resistor 2. Capacitor uses to blocking dc current to preamplifier See picture below for better understand. However, an output signal from the microphone is very small and need to amplify with any preamplifier before connecting to amplifier board. Now, let's start making and preamplifier. -------------------------------------------------------------------------------------------------------------------------- Above picture shows how to bias opamp for single power supply (V+ and Ground) ...
Read more

PAM 8403 board amp wiring diagram

-
Image
PAM 8403 is a portable 3 watts stereo class d amplifier that uses only 5 volts D.C. to operate. The amplifier board is easy to wiring and very small size, you can make a small amplifier project that not requires high voltages to work. The first thing you need to know. PAM 8403 cannot bridge together because the amplifier is already bridge-tie-load output configuration Over 6 volts can damage the amplifier module, if you want higher power you can check 10 watts class d amp PAM 8610 here You must use shield wire connect from input source to volume control and from volume control to the amplifier board input if you don't want your amplifier to suffer from parasitic oscillation (sound like JeeeeJeeee) Today I will show you how to wire PAM 8403 board amp that easy to understand. Let's see image below. You can see that two speakers do not share output ground like normal amplifier because PAM 8403 is a  bridge-tied-load amplifier, if each speaker wire touches eac...
Read more

10 watts 8 ohms class d amplifier pam8610 sound test

-
Image
Pam8610 IC is 10 watts @ 8 ohms (15 watts @ 4 ohms small heat sink require) stereo class d amplifier with very high efficiency over 90% and the amplifier works well without any heat sink at full power!!! . The amplifier board is very low cost ( around 1 $) but deliver 10 watts @ 8 ohms power from 13 volts power supply. As you can see in my video that the amp board require only one 100 uf electrolytic capacitor for supply decoupling to eliminate hum from switching power supply(some ic amplifier require 1000 uf to eliminate hum from the power supply). Sound testing: The amplifier sound good with good bass respond  good bass impact and well control (kick bass very good). High frequency clean, impact well and flat but lack transparent. Singer vocal is clean but not transparent. The sound stage is wide but space between instrument not precise. pam 8610 amp board is the quiet amp with very less hiss noise (5 cm away from tweeter to my ear :) which is not a big problem at all and ...
Read more

How to make a simple audio pre-amplifier

-
Image
I saw a comment on my video that he wants a high-gain audio amplifier (1000 times or 60 dB voltage gain!!!). However, most commercial power amplifier IC has a maximum fix gain of around 200 times (lm386) which is far from 1000 times voltage gain, and the problem when you make a high gain amplifier is the high-frequency roll-off problem. The solution to the problem is making a pre-amplifier that has very low distortion, and wide bandwidth, and it can amplify audio signal around 10 times or 20 Dbs and send the audio signal to a power amplifier (the power amp IC he uses is tda7052 that has 40 dB or 100 times voltage gain). When combining the voltage gain of the two amplifiers, he will get 1000 times the voltage gain audio amplifier!!! The method is easy and uses minimum electronic components Breadboard wiring Audio preamplifier circuit diagram. Electronics component list: IC 1 = NE5534(op amp ic) R1, R2, C3 are amplifier gain control by negative feedbac...
Read more