IR Beacons help!

Hello :smiley:,

I bought a pair of IR beacons, and they work very well.
My problem is that i want to disable in one beacon the IR transmitters to save energy (im very limited) and make it only unidirectional… Any mha saved could do the difference.
Any way i tried to remove the Q1 (component) from the board to disable the IR transmitters, but after, when i power on the beacons the 4 red leds just blink, like saying: “Hey there is an error!”… I connected the “transistor” again and the beacon work again…
So i move to plan “B” and try to make my own beacon receiver, i bought the sensors TSOP34156 from here, and i connect it directly to my microcontroller (atmega168v@8mhz), i followed the schematics from pololu, i putted the 47 ohms resistor in the 5Volts, and a capacitor of 10 uF to ground(i don’t have other one). I programed a quick code and seems to be working well… The problem is when i power on the original transmitter Pololu beacon, all the pins got HIGH, so i program a code to read the Pulses length, but i just obtain random values (if i use my tv control i obtain regular values).
There is any suggestion or idea??
I will appreciate your help guys… Thanks!!


The IR beacon does the self-check you mention, but the LEDs should just flash a few times to indicate the error and then continue with normal operation, so your MOSFET removal approach should have worked. Are you saying the red LEDs kept flashing forever?

- Jan

Hi Jan, thank you for your answer.

Yes the four red leds keep flashing forever… Till i reconnect the transistor…

The other trick i tried is connect the 5V directly into the ICSP header PIN-2(to void the voltage regulator and the IR diodes), but the same the 4 red lights keep flashing forever…

I just need to be able of power the unit using 5V and remove the IR transmitters…

(Maybe you should sell an unidirectional version of the beacons, obviously a cheaper price :unamused: )

Right now i’m trying to setup my custom beacon… But i still getting nothing usable…

Can you explain me a little bit of how can i use the IR sensors with the transmitter beacon, please?

Thanks again…

The LEDs flashing forever sounds wrong; I’ll look into it in a bit.

To use the sensors yourself, you want to see which of your receivers sees the most activity. The beacons send all kinds of IR pulses (that’s why you’re not seeing regular values as with the TV remote), and the idea is that the IR detector facing the other beacon will see the biggest number of the pulses. For instance, you could poll all sensors every 100 us and keep the totals of the number of times each is active. Do that several hundred times, and then pick the one with the highest count. If no count is above some minimum you set (to account for some spurious activations), you can decide that the transmitter is not visible at all.

- Jan

That is exactly what i did… :smiley:

Check the video here:

i added the video the past saturday, March 15.

Thank you very much for your time and help…

thinking of getting the ir beacon development board ,can i get the firmware code,to make it work with my design

Unfortunately, we do not have any publicly-available code for the IR beacons. However, the “to make it work with my design” part of it should be most of the work anyway since the only hardware on the board is the IR LEDs, which you’ll have to flash according to your application.

- Jan