Simple doorbell Using UM66
Below is a simple circuit of doorbell using UM66. The circuit can be assembled in a general purpose PCB and enclosed in any toys. Parts C1 – 220 µF 10v VR1 – 100 k pot VR2 – 10 k pot…
A home to software testing, electronics circuits & projects, tips and tricks and digital diary.
A home to software testing, electronics circuits & projects, tips and tricks and digital diary.
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Linux Essentials for Testers
As a software tester, knowledge of basic Linux commands is a necessary. Before going in to details commands we should be aware of some of the facts of Linux OS. Facts You can do almost anything in a terminal which…
How to force install apps to SD card without ROOT
Force install apps to SD card without ROOT Samsung Galaxy Ace has only got 180 MBs of Internal memory. If you install a lot of apps, you are bound to run into low disk space issues. To force your new…
LED Torch with adjustable brightness
The Led torch with adjustable brightness circuit uses LM3914 as the basis of a 10 step variable brightness current-regulated white LED . This circuit has only four components in the control and regulation circuit: R1,R2, VR1 and LM3914. Part List 1.…
Mains Powered LED Lights
All mains powered LED circuits work with 240 volt AC current. Mains powered LED – Single LED The power diode in the first diagram is designed to discharge the 220n during one half of the cycle so that the capacitor…
Audio Amplifier using LM386
Audio amplifier using LM386 is a power amplifier designed to be used in low voltage consumer applications. Typical applications are like portable AM/FM amplifier, TV sound systems. It requires minimum external parts and operate from wide range of voltage starting…
White LED on 1.5 v Supply
In this post you will find circuit on how we can light up white LED on 1.5 v supply. Heart of the circuit is the transformer winded on 2.5mm by 0.5 mm core using 0.095 mm wire. 2 White LED…
Flashing LED
Alternate red and green flashing LED using 9 volt battery Part list R1,R2 – 100 Ohm R3,R4 – 105 K C1,C2 – 10 μF 25 Volt T1-T2 – BC 548 D1-D5 – Red LED D6-D10 – Green LED 9 Volt Battery
Dark Sensor
Dark sensor using 2 transistor BC547 When light falls on LDR, its low resistance drives the transistor T1 into conduction. This keeps transistor T2 cut-off due to low base bias. The LED does not get power as long as ambient light…
LED Flasher using NE555
LED Flasher circuit using NE555 timer IC R1, R2, C1 and the supply voltage determine the flash rate. For a variable flash rate, replace R1 with a 1 MΩ pot in series with a 22k resistor. The purpose of R3…