Buffalo IR sensors and connecting blocks: great!

Guy Lavoie

Active Member
Through a special arrangement with Martin at Automated Outlet, I got to try out the Buffalo Electronics IR connectivity devices today. In one word: these are versatile, no nonsense devices that work well.

These devices are very similar to (and interoperable with) Xantech basic IR distribution devices. The product line is actually quite straightforward: two different types of IR receivers and one universal, amplified connecting block. You can also get standard stick on emitters and a "junction box" to connect up to 9 IR detector devices together.

First the IR detectors: one model is designed to be mounted through a 1/2" hole for almost invisible in-cabinet mounting, while the other is designed to be mounted in a standard electrical box, presenting a "Decora" style flat faceplate. The face plate has a small (about 3/16 by 1/8 inch square) opening for the IR detector and a tiny pinhole in the center with a LED for visual feedback of a received IR signal. Each detector device has a three screw terminal wiring strip: +V, Gnd, and signal out.

The connecting block has a power input jack (for a 9 to 12 volt DC supply, Buffalo sells a 9 volt wall wart), a three screw terminal wiring strip, and 4 mini phone plug jacks for emitters. Wiring is simple: just connect the +V, Gnd and signal terminals of each device (IR detectors and connecting block) all in parallel. That's it. You can easily test the operation by aiming a remote at one of the IR receivers and observing the "signal" LED on the connecting block, which will blink in real time with the received signal. One slight oddity is that the order of the three screw terminals is not the same on the connecting block and on the IR receivers. The center terminal is Signal on the IR receivers and Gnd on the connecting block. Just make sure you wire them correctly.

After doing some initial tests, I wanted to see how easy it would be to hook up to an Ocelot IR output. A test with a scope shows that the signal line is active high, which means it stays at ground level unless there is an IR signal. The Ocelot's IR output is also active high, but at 5 volts instead of 9. I made up an "interface" cable consisting of just a mini phone plug with a signal diode to isolate the Ocelot's output (anode to Ocelot, cathode to connecting block) and connected that in parallel with the IR detectors. It works just fine, with no loss in signal strength at the outputs. Thats the nice thing about an amplified block such as this one. Note that a SECU16IR output is not a active high signal, so interfacing an output on that would not work the same way and need a different circuit.

Finally, I proceeded to connect one of my infamous home made IR blasters directly to one of the output jacks and that also worked fine, sending the signal across the room. Note that the connecting block's output is actually open collector (pulling down) with the current limiting resistor apparently on the + side, so there is no common ground between the connecting block's ground and the blaster circuit, so you cannot use the same power supply to power both devices. Still, the simplicity with which it can be connected was a pleasant surprise.

These devices work well and have a solid, well built feel to them. Just the weight of the devices and thick metal brackets give a good impression. The hole mounted IR receiver is machined out of a solid brass tube. Martin has good prices on them too. Just look up "Buffalo Electronics" under the home Automation category.
Guy, I also want to try these out (haven't had the opportunity yet). I would like to connect the block to my Ocelot as well. Would you mind showing a schematic of the components and how you integrated them with the 1/8" jack (sorry, I'm better with pictures and I don't want to damage my Ocelot!).


The integration I did was from Ocelot IR out to Buffalo input (as if the Ocelot was just another Buffalo IR receiver). It is very simple:

mini plug

tip -------------|>|--------------------- signal (Buffalo input)
ring------------------------------------- Gnd

The diode is an ordinary signal diode, such as a 1N914 or 1N4148

The +V connection from the connection block is not used for the Ocelot, and you can still connect several Buffalo IR detectors in parallel with this connection.

To go the other way (ie: from a buffalo output to the Ocelot's IR input) I would simply suggest to use a mini emitter stuck to the Ocelot's IR receiver window.