This is basically a high gain amplifier with feedback that causes the LED to light and flash at a rate determined by the 10u and 330k resistor.
Remove one of the transistors and insert the unknown transistor. When the transistors are inserted with the pins in the correct position as shown in the photo, the LED will flash. To turn the unit off, remove one of the transistors.
1 – 10 uF polarized capacitor
1 – 1K ohm resistor
1 – 330K ohm resistor
1 – 22 ohm resistor
Read More, See Schematics and Video...
Simple Transistor Tester
Pretty Cool little Tool!:)
- Simple transistor tester makes sorting easy
- Simple transistor tester makes sorting easy - Hack a Day
- HACK A WEEK » Blog Archive » Hurricane Evacuation Kit
- HACK A WEEK » Blog Archive » Simple Transistor Tester
- Simple Transistor Tester - YouTube
- HackaweekTV's Channel - YouTube
- Digital Multimeter - Save on this 7 Function Digital Multimeter