Uploaded June 2015 | Updated September 2026, 1 week ago

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After a comment was left on my previous SJR3 video, I decided to look at the circuit again and build a smaller version. Here's the original video: youtube.com/watch?v=5Mp1N6mdSZI

Several ferrite beads were found on an old computer board and they were desoldered, then stuck together with glue.
300 turns of 40AWG first layer, 120 30AWG as the second layer.
See LaserHacker.com for the schematic.

Transistor is a C2690A
Doesn't get warm at all and no heatsink is required.