Biquad ant. for WLAN

Biquad Antenna for 2.4 GHz - 802.11b/g - WiFi - WLANAfter some research, I found out that the simplest type ofhomemade WLAN antenna is BiQuad antenna. Many sites provide goodinstruction on how to assemble it.(refer below)a href="http://martybugs.net/wireless/biquad/" title=""Biquad Antenna Construction" target="_blank">Biquad AntennaConstructiona href="http://flakey.info/antenna/biquad/" title=""Biquad Sector antenna for 2.4 GHz" target="_blank">Biquad Sectorantenna for 2.4 GHza href="http://www.sorgonet.com/network/biquad/" target=""_blank" title="Building a biquad antenna for wireless 802.11b">Building a biquadantenna for wireless 802.11ba href="http://www.trevormarshall.com/biquad.htm" title=""Trevor Marshall BiQuad 802.11b Antenna">Trevor...

Read more »

ATX PSU Diagnose

About ATX Power SupplyATX Power Supply converts the wall (AC) to the direct current (DC) needed by thePC. The power supply looks like a metal box with fan.Typical computer power supply generates the voltages needed by the computer motherboard accessories.[Read more...]Before EverythingDisconnect all socket from your main board, HDD, CD/DVD drive, Floppy drive and etc so that we can isolate which partis not working.Step 1 - Check Wall AC powerTo check this, you may try to plug in any electrical appliances to the wall socket to verify that the 240V existsuch as lamp, table fan or etc. If it is working, that mean the power from the wall socket is ok.You may also check the voltage with multimeter if you have one.Step 2 - Power Socket FuseIf you...

Read more »

S/PDIF - TOSLINK interface

Circuit & Information on TOSLINK interfaceSo you want to get a high quality audio for minidisc recording but whenusing red and white RCA, the quality drop drastically. Here a my cheap solution for you.Actually you can find a lot of references of this type of simple project in the internet.REF* S/PDIF = Sony/Philips Digital Interface* TOSLINK = ( TOSLINK Interconnect History & Basics)* Another web offering the same information* SPDIF at epanorama.netMeet my version of cheap, 2 components TOSLINK @ S/PDIF.Try to find a cable with connector from old PC casing for this.(HDD led,reset switch or power button connector)Assemble it using your own creativity. Use the pen tube for the light transmission.Connect it to the back of your CDROM...

Read more »

PC IrDA interface

DIY IR interfaceThis circuit is also from www.electronics-lab.com.Since it is very hard for me to get the infrared interface (TFDU4100), I start to look in the old/damage handphones.It looks something like this.Now, you need to remove it using the hot air blower perhaps.Connecting to motherboardPlease refer to www.electronics-lab.comon how connect this irda module to your motherboard.My IrDAInfrared Transceiver ModulesHere are the pin layout and picture of the device.Pin Description of TFDU4100 Pin Number Function Description I/O Active 1 IRED Anode IRED anode, should be externally connected to VCC2 through a current control resistor 2 IRED Cathode IRED cathode,...

Read more »

Touch Switch

Experiment With NAND Gate - CMOS 4011Output goes high when touch wires bridge by fing...

Read more »

Gates Oscillator

Experiment With NAND Gate - CMOS 4011(CMOS 4011 Layout)CircuitTry this super-simple experiment. The output frequency is about 1kHz (square wav...

Read more »

Telephone FM Transmitter

Descrition & CircuitThis project is taken from www.electronics-lab.com.With some modification, I create my own version of FM Telephone bug complete with stripboard layout.Theortically, the frequency range is from 88MHz to 94MHz but you may experiment with the coil structure to tune it Circuit Strip Board Layout Parts List Diode IN4384 4 LED 1 Resistor 12k 1 1k 1 200R 1 Capacitor 470p 1 330p 1 25p 1 12p 1 Transistor A933(PNP) 1 Coil *See note 1*Coil note7 or...

Read more »

Lab Power Supply

Description and CircuitMake your own lab power supply complete with adjustable voltage and constant current source.Using single IC (LM324)Here is the circuit.Strip Board Layout.Part List1 LM324 Opamp1 Ammeter 100 µA 1k ohm1 Voltmeter6 IN40011 Zener Diode 9.1V1 Full-Wave Bridge Rectifier1 LED2 NPN Transistor, 2N30551 NPN Transistor, BC109C1 Transformer2 E-Capacitor 2200µF1 Potentiometer 5k ohm linear1 Potentiometer 10k ohm linear1 Resistor 500 ohm2 Resistor 2.2k ohm1 Resistor 560 ohm1 Resistor 6.2k ohm2 Resistor 68k ohm1 Resistor 0.22 ohm4 Resistor 4.7k ohmComponent Image. LM324 2N3055 Some Pictur...

Read more »