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Help IR Beacon Transceiver

Hello,
I need help. I am trying to use the beacon pairs with arduino with my students in an engineering class. I bought the sensors but neglected that they needed 6V-16V and the board only provides 5V. So then I plugged them into the VIN pin on the Uno board and powered the board with a 9V battery. The sensors then worked and could sense a TV remote, but not the other beacon. I need to be honest and admit the the direction lights when I use a TV remote are not reliable - they mostly light up 180 degrees from where the remote is (perhaps the signal is bouncing off something?

I then powered the other beacon with a second Uno board (as will happen when students use them to sense a cat and mouse robot) but the beacons do not detect each other and I cannot see a regular IR transmission signal as is shown in the demonstration video that is posted on the product page. What am I doing wrong?

Is the enable pin required for the beacon to transmit a signal?
We tried this without the lights on to test to see if fluorescent lights were interfering, no difference, still same problem.

Is it possible the 9V battery doesn’t provide enough amperage?
I know these should work with the code and wiring setup I have but cannot seem to get them to detect each other.
Any advice? I need to get two detectors to detect each other so students can play cat and mouse and not sure what the next steps are.

Hello.

A 9V battery is definitely not appropriate for powering these boards. The LEDs, on the IR beacon draw current in large bursts, and 9V batteries cannot supply much current, so the voltage is probably dropping substantially (can you look at what’s happening there on a scope?). Can you try testing your boards with a suitable power supply?

- Patrick

Thank you! sorry to be ignorant but what would be suitable power supply on a small robot?

I do not how big your robot is or what else is on it, but for the IR beacons we generally recommend AA or AAA NiMH batteries or battery packs or 2S or 3S LiPos.

- Patrick

Thank you for responding. we have tried AA pack with 4 batteries (6V) to power the arduino board. With 6V from the VIN pin into the sensor, we get no detection and cannot see any IR signal from the beacon with a cell phone camera. with the AA batteries the sensor doesn’t seem to detect a TV remote at all, so we thought it might be not enough voltage. Any idea what could be wrong? we tried it with setting the enable pin on and without the enable pin

The robot is tiny - just the size of the board with two gear motors with arduino. Do you have any pictures or images of using this with arduiino?

I suspect the pack voltage is not high enough. What is the actual voltage of the pack when you measure it with a multimeter? Can you look at what the power is doing on an oscilloscope?

- Patrick

Thank you for the help troubleshooting. Connecting the beacon with 4 AA batteries external power yields 6.42V from brand new batteries and then we detect the beacon emitting IR. The beacon with this external power at 6V will not detect the TV remote. But it will detect the TV remote when we put 2 6V packs in parallel (still 6.42 V). We do not have a scope, just a multimeter.

I am glad to hear that you got your IR beacons working! You might consider putting a few more batteries in series to ensure that it will maintain a high enough voltage as the your batteries are used, and maybe that will help the situation with the TV remote so that he does not need the extra batteries in parallel.

By the way, you can get a decent oscilloscope these days for a few hundred dollars, so we strongly recommend you invest in one. In this case we were able to resolve the issue without one, but using a scope will save you a lot of time and give you better understanding of your systems, which enables better designs, better margins of operation, etc. Without one, you’re left mostly just guessing about what might be happening, which is not a great way to operate. Also, a scope would also be a great way to demonstrate electronics concepts to your students.

- Patrick