Category Archives: Sheme


BIKE FLASHER – Amazing! This bike flasher uses a single transistor to flash two white LEDs from a single cell. And it has no core for the transformer – just AIR! All Joule Thief circuits you have seen, use a ferrite rod or toroid (doughnut)


BIKE FLASHER This circuit will flash a white LED (or 2,3 4 LEDs in parallel) at 2.7Hz, suitable for the rear light on a bike.   Source:


12v RELAY ON 6V SUPPLY This circuit allows a 12v relay to operate on a 6v or 9v supply. Most 12v relays need about 12v to “pull-in” but will “hold” on about 6v. The 220u charges via the 2k2 and bottom diode. When an input


3v WHITE LED FLASHER This will flash a white LED, on 3v supply and produce a very bright flash. The circuit produces a voltage higher than 5v if the LED is not in circuit but the LED limits the voltage to its characteristic voltage of


1.5V LED FLASHER This will flash a LED, using a single 1.5v cell. It may even flash a white LED even though this type of LED needs about 3.2v to 3.6v for operation. The circuit takes about 2mA but produces a very bright flash. My

LM2596S DC 5V-36V to DC 1.5V-33V Step down converter

U1- LM2596s C1- 50V 100uF kondezator C2- 35V 220uF kondezator C3- 0.1uF (104) kondenzator C4- 0.1uF (104) kondenzator D1- 3.0 A Schottky Barrier Rectifiers D2- led dioda L2- 47uH induktor (470) R1- 1KΩ otpornik R3-  330Ω otpornik RV1- 10KΩ Podesivi otpornik

Precizno napajanje 0-30V, 0-3A

0-30 VDC STABILIZED POWER SUPPLY WITH CURRENT CONTROL 0.002-3 A ALL INFO ON SOURCE PAGE: ELECTRONICS-LAB.COM Input Voltage: ……………. 24 VAC Input Current: ……………. 3 A (max) Output Voltage: …………. 0-30 V adjustable Output Current: …………. 2 mA-3 A adjustable Output Voltage Ripple: …. 0.01

Podešavajući DC-DC Konverter (Step Up Converter)

U1 LT1370HVCT7 il slican (step up/ step down regulator) C1,C5- 470uF 50V C2,C6- 10uF C3- 47nF C4- 4.7nF L1- 10uH D1- STPS5L60 ili slicno R1- 2k R2,R3- 390ohm R4- 10k Ulazni napon od 5V nadalje, izlazni 30V  

Podešavajući DC-DC Konverter (Step Down Converter)

U1 LM2678T-ADJ C1- 220uF 50V C2- 10uf C3- 10nF C4- 1000uF 50V C5- 10uF D1- 60V 5A SCHOTTKY Dioda (STPS5L60 ili slicno) L1- 22uH 6A R1,R2- 1kOhm R3- 10kOhm Ulazni napon je 30volti maksimalno, a izlazni je od 2.5v do 14v 3A

Jednostavni Termostat sa dva tranzistora

  Parts List: Part Description Radio Shack # DigiKey # Notes R1  1K resistor  brown black red gold R2  1K, NTC R3  10K resistor  black brown orange gold P1  10K trim pot  bourns, multi-turn D1  Led, red  Light Emitting Diode D2  1N4148 diode  276-1101  1N4148DICT-ND

Regulator struje (Booster)

Volt regulators such as the LM708, and LM317 series (and others) sometimes need to provide a little bit more current then they actually can handle. If that is the case, this little circuit can help out. A power transistor such as the 2N3772 or similar