Handy IR Tester

Michael 2727

Senior Member
I sent this design to Silicon Chip late last year.
I think it appeared in MAY 07 Notebook circuits.

It was purposed designed for a friend to test
out his customers Remote Controls at a Video/
DVD hire shop.
I designed it as a simple point and shoot IR
Remote tester.
It will not decode IR signals but you can use
it to see and hear the IR Pulses via the piezo
and Red indicator LED.

The other main feature is that it can be left plugged
into a 9V PP3 battery and will draw virtually NO power.
As long as bright light is not shone directly into the IR LED.
(mine sits on a shelf, under a 60W Bulb without any problems,
10 months later, original battery and always ON)
The reverse biased IR LED is used as the IR Detector here.

The Detection range is short 10mm to 300mm or 1/2" to 1' Foot
if a standard IR Remote is pointed at the IR Detector LED.
(Sorry Stan, no trans Tasman applications here)

Not a Picaxe design but may be a handy tool
for debugging your next Picaxe IR application.



Senior Member
Neat circuit. I can’t help but be impressed when I see the incredibly high gate resistance of FETS exploited like this.