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Infrared remote control jammer
This device was developed to preserve our sanity when
our grandson or younger family members come to visit.
They love watching childrens TV channels at high volume
levels, resulting in an amazing amount of highly irritating
sounds. The result is continuous cries of “turn it down”,
only to have the volume slowly turned up again over the
course of a few minutes.
This device sends out a 15-second burst of infrared at
around 38kHz whenever the volume up button is pressed
on the remote control. This swamps the IR receiver in the
television, stopping the volume increasing.
To successfully turn the volume up, two buttons on the
remote must be pressed first (in either order), then the volume up button. I chose the yellow and red buttons on my
TCL brand remote. Note that as soon as another button is
pressed, for example to change channels, the device reverts
to jamming mode.
I also had to disable the manual volume up button on our
TV as our grandson soon worked out that he could turn the
volume up that way!
The circuit is simple – the infrared receiver and IR LED
are both powered from the Arduino’s 5V supply. The receiver feeds remote control codes into digital input D11 while
digital output pin D8 drives the IR LED via NPN transistor
Q1, with a 270W base current limiting resistor and a 10W
LED current limiting resistor.
I built my device inside a plastic box and powered it from a
USB power supply that goes to the same socket as the television, so the circuit has power whenever the TV is plugged in.
The infrared LED needs to be reasonably close to the TV,
and ideally hidden to avoid sabotage. The software code is
commented to show where to enter the required infrared
codes to suit other TVs.
You will need to use the included IR decoder sketch
(which I did not write) to determine the codes produced by
your remote control. Both sketches are available for download from siliconchip.com.au/Shop/6/5821
Geoff Coppa, Toormina, NSW. ($75)
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