I built two  remotely controlled flashlight for a Halloween game.

For that I added a micro-controller in flashlights, which would receive the signal from an IR remote, and switch on/off the light (with a flickering fading pattern).

====== flashlights ======

the circuit is really simple:
  * Unordered List Iteman infra-red demodulator (38 kHz, to be compatible with most remotes)
  * a transistor to power the light (nMOS)
  * a micro-controller to decode the IR command and switch the lights.

For the micro-controller I used an Atmel ATtiny85V.
This can directly work with 2xAA batteries (2.0-3.0V) and 3xAAA (3.0-4.5V).
Thanks to its small size it can be installed inside the flashlight.

===== 1st prototype =====

this was more a proof of concept.
it used an old incandescent-bulb-based flashlight.
since the case is transparent, the IR receiver can also be placed inside.

{{:remote_flashlight:prototype-1.jpg?0x250|}}
{{:remote_flashlight:circuit-1.jpg?0x250|}}


===== 2nd prototype =====

this uses a more robust flashlight in an aluminium case.
the LED in the center has been replaced by the IR receiver.

{{:remote_flashlight:prototype-2.jpg?0x250|}}
{{:remote_flashlight:circuit-2.jpg?0x250|}}
{{:remote_flashlight:receiver-2.jpg?0x250|}}

===== firmware =====

two firmware versions have been writte:
  * the {{ :remote_flashlight:firmware_nec.tar.bz2 |first}} to receive commands from more common remote controls using the IR NEC protocol
  * the {{ :remote_flashlight:firmware_nikon.tar.bz2 |second}} to receive commands from the more task appropriate Nikon shutter remote

====== remote ======

===== Nikon =====

{{:remote_flashlight:overview.jpg?0x250|}}

to remotely control the flash light, I used a Nikon remote control.
it was originally intended to trigger the shutter of some Nikon camera.
but I re-used it because the form factor and single large button fitted my use case.

{{ :remote_flashlight:ir-nikon_trace.zip | here are sigrok traces}} of the IR signal transmitted by the remote.

===== TV-B-Gone kit =====

to be sure the operator could remotely control the flashlight in all circunstances, I also provided a [[https://learn.adafruit.com/tv-b-gone-kit|TV-B-Gone (Kit)]] {{ :remote_flashlight:firmware_tvbgone-nikon.tar.bz2 |re-programmed}} to only send the Nikon code (at very high power).