Introduction: "Joule Thief" - No IC and No Transformer
Yep, no transformer and no hard to get IC. But, ... two transistors and other parts are required. I actually found this circuit by accident while roaming Colin Mitchell's Talking Electronics website (talkingelectronics.com). This website is very rich with examples and explanations of a huge variety of circuits. In fact, this website is so abundant in circuits that later on, I couldn't find the circuit revealed here. Anyhow, I believe that the TE circuit can be considered "robust" as it works even if different parts are used.
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With an ordinary red LED in series with the white LED, the circuit draws 15 milliamps @ 48 kHz.
But when using only the white LED, the circuit draws 17 ma @ 38 kHz.
The "Joule Thief" circuit using only easily found parts and no transformer might be attractive to many readers here. This is why I thought it was important to reveal this project.
But in my case, I am still tilted toward the simplicity of a "Joule Thief" circuit using little more than an IC and an Inductor, as revealed in my Instructable, "Joule Thief" Circuits - crude to modern...