A Strobe flasher for bike indicator

Simple circuitry allows the project to be built at low cost in a lightweight, compact
package that can be secured to the bicycle or the rider's belt. 
The light from this circuit uses a xenon tube to generate a bright flash that can be
seen from a great distance - but is not intense enough to destroy a driver's night vision.

Circuit 



Parts Lists

Build your own this low cost analog capacitance meter


When a capacitor is connected to a constant-voltage source through a resistor, the charge on the capacitor increases exponentially. If the source supplies a constant current, however the charge on the capacitor increases linearly. This linear charging principle is used here in the design of capacitance meter which will measure values outside the range of most such meters. 

By using a constant-current source, the meter determines the time it takes to match the charge on the unknown capacitor to a known reference voltage. The meter has five full scale range o 1, 10, 100, 1000, and 10,000 uF.on the 1-uF scale , values as small as 0.01 uF can be read easily.

The Circuit 
 




Power Supply




Parts List



PCB Layout



Component Layout 



Prototype:


source :  Electronic Experimenters Handbook 1980 edition 

Best TP Link Archer Wireless Router Series

We pick 10 best TP-Link Archer Series . TP-Link Technologies Co., Ltd., is a Chinese manufacturer of computer networking products based in Shenzhen, Guangdong, China.

1.  TP-Link AC1750 Smart WiFi Router (Archer A7)

Dual Band Gigabit Wireless Internet Router for Home, it Works with Alexa, VPN Server, Parental Control, QoS

With parental controls and guest access.Keep your family safe and devices secure with advanced WPA/WPA2 wireless encryption.

Delivers Up to 2,500 sq.ft. exceptional WiFi coverage  throughout your home as three high-gain antennas and strong amplifiers connect every device—from the living room to the backyard. Check It Out

White LED Lamp Circuit

Make  this  solid-state pocket torch using a few of these white LEDs. The simplest approach is naturally to use a separate series resistor for each LED, which has an operating voltage of round 3.5 V at 20 mA. Depending on the value of the supply voltage, quite a bit of power will be lost in the resistors. 

The converter shown here generates a voltage that is high enough to allow ten LEDs to be connected in series. In addition this converter supplies a constant current instead of a constant voltage. 

A resistor in series with the LEDs produces a voltage drop that depends on the current through the LEDs. This voltage is compared inside the IC to a 1.25 V reference value, and the current is held constant at 18.4 mA ( 1.25V devided by 68Ohm)
The IC used is one of a series of National Semiconductor 'simple switchers'. The value of the inductor is not critical; it can vary by plus or minus 50 percent. 220 uH coil at 3.5 A is good choice. Almost any type of Schottky diode can also be used, as long as it can handle at least 1 A at 50 V. The zener diodes are not actually necessary but they are added to protect the IC. If the LED chain is opened during experiments, the voltage can rise to a value that the IC will not appreciate.

Circuit


PCB Layout



Component Layout



Parts Lists


source ; Elektor 

Free Energy : Centrifugal dynamic power generating system using a lever structure Patent

This patent of Centrifugal dynamic power generating system using a lever structure invented by Daniel Paul Gorney. 

The free energy concept is the system/machine that operate perpetual motion indefinitely and independently without any other source of fuel, electricity, or any other renewable energy source other than gravity energy.

The free energy magnitude is over unity concept. the free energy result must bigger than energy for running the system/machine itself.