This is my high power take on the TV-B-Gone, a wonderful open source project brought to us by Mitch Altman.
I had a couple of good chats with Al about this and here are some thoughts:
- LED only tends to be on about 50% of the time due to the 50% duty cycle of the 38kHz carrier.
- A current regulator is overkill for this application and an inductor will interfere with the carrier.
- A simple resistor will suffice for the brief bursts.
- A power resistor is required though as there's some serious current through, and voltage drop across, this resistor.
- Al and I came up with using four 24 ohm 1206 resistors in parallel to be able to put them on the PCB and keep the size down.
- This is predicated on a derating for the 50% duty cycle of sending IR codes and will fail is powered continuously.
- An 18650 should be able to power this perfectly well.
- Perhaps making use of an existing flashlight body would save from needing to design and print a flashlight enclosure.
2026-05-24
: completed schematic design and started PCB layout using KiCad.