Today we released a new patch for the Fon firmware. We have included OpenVPN in the firmware so your Fonera can now act as an VPN server! Download and read more here.

Based on the classic Baxendall tone control circuit, this provides a maximum cut and boost of around 10dB at 10K and 50Hz. The first [url=http://www.chinaicmart.com/suppliers/174/BC109C.html]BC109C[/url] transistor (left hand side) is acting as a buffer. It provides the circuit with a high input impedance, around 250k has a voltage gain of slightly less than unity. As the Baxendall tone control...
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This timer makes a LED be on for a certain amount of time after pressing the switch. This time is adjustable from 3 seconds to 2 minutes using the potmeter. Instead of a LED other load can be connected to this circuit, a relay for instance. [url=http://www.circuitdb.com/download.php?fileID=217]TinyCAD file of this circuit[/url]

Building a serial port interface. Mount network shares. Build your own modifed firmware for La Fonera while keeping the original Fonera functionality.

CircuitDB is proud to announce that saurabhparashar is the winner of the CircuitDB Design Contest 2008! He sent in his Programmable path navigator Robot project. Congratulations saurabhparashar! You win 100 US dollar and eternal fame!

Here is some good news for WiiKey owners, http://wiikey.cn is up again! They also have released an update that should fix the problem with original Super Smash Bros Brawl disc and add a DVD update blocker to prevent a NTSC disc to ruin your PAL Wii. Just to be sure CircuitDB will continue hosting the files here.

The object of Quick Draw is to test your reaction time against your opponent's. A third person acts as a referee and begins the duel by pressing S1, which lights LED1. Upon seeing LED1 go on, you try to outdraw your opponent by moving S2 from "Holster" position to "Draw" position before your opponent moves S3 from "Holster" to "Draw" position. Who ever gets...
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This circuit will give you a feel for how the touch plate works in a circuit and you can expand on the circuit to suit your project needs. The touch plate can be a small piece of metal or aluminum foil. Start the circuit by moving S2 to the set position and then back to the previous position. Now press S1. One of the LED's will light. Now touch the touch plate and the LED's will flip on the...
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The speed of an automobile can be indicated by detecting the pulses generated by the ignition system and causing an LED to light. The circuit utilizes a quad NOR gate IC chip. Two of the gates are configured as a one shot multivibrator which produces a fixed duration pulse each time the primary circuit of the automobile ignition system opens the circuit to the ignition coil. The other 2 gates are...
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This circuit simulates the siren of an American police car. It uses two 555 timers in the circuit. The 555 on the right is wired as an alarm tone generator and the second 555 timer on the left is wired as a low frequency astable timer which generates a ramp waveform of about 6 seconds that is buffered by the transistor and again used to frequency modulate the tone generator. The transistor is...
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This circuit simulates the "Red Alert" siren from the TV show Star Trek. It uses two 555 timers in the circuit. The 555 on the right is wired as an alarm tone generator and the second 555 timer on the left is wired as a 1.5 second non-symmetrical astable that generates a fast rising but slow falling saw tooth waveform. This waveform is buffered by the transistor and used to frequency...
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This circuit simulates the siren of a British police car. It uses two 555 timers in the circuit. The 555 on the right is wired as an alarm tone generator and the second 555 timer on the left is a 1 Hz astable multivibrater. The output of the left timer is to frequency modulate the right timer. This causes the right timers frequency to alternate between 440Hz and 550Hz at a 1 Hz cyclic rate. The...
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Ever needed a low power 120volt AC power source for your car, van or truck? Well this circuit should do the trick for you. It will supply 15 watts of AC power to a device. It should power lamps, shavers, small stereos and small appliances. If you draw to much power the circuit will shut down all by itself. The output of this circuit is a square wave so there may be some noticeable hum on audio...
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The ISD1000A is a Direct Analog Storage device which allows you to store 20 seconds worth of voice data on an IC chip which can be play backed anytime. The data stored will stay in memory even if the power is removed. To use the circuit below simple apply power to the circuit, press the record button and hold. Speak clearly into the microphone. You have up to 20 seconds of voice message that you...
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Stick the metal probes into a freshly watered plant and adjust R5 for a mid-scale meter deflection. The meter will monitor the soil wetness and the meter will indicate whether it is to moist or to dry. This circuit uses a dual power supply which could be created by two 9 volt batteries. Copyright 2000 [url=http://home.maine.rr.com/randylinscott/index.html]Randy Linscott[/url]