Joule Thief: Supplement: Burst Oscillations in the Clothespin JT, AG1 Cell
A version of AcmeFixer’s JT design, built onto a clothespin for “ease” of connection to a button cell battery, demonstrating an interesting effect on the “dead” button cell.
Transistor is BC337-25. Toroid is 3/8″ OD from a CFL, stripped and rewound with 5 + 5 turns of #27 enamelled magnet wire, measured inductance about 45 uH each winding. Resistor is 1500 ohm carbon comp. from TV chassis. Diode is 1n4148, osc cap is 1 nF 50V monolithic, reservoir cap is 47 uF 20V tantalum, LED is white. Battery is AG1/LR621 alkaline cell from Harbor Freight. Clothespin is wood.
Schematic and discussion at