I have tried to figure out how to do this, but have had no luck with my brief testing. Has anyone tried using the output of the USB UIRT to connect to the signal in on the RP6. I cut an emitter I had, and connected the two ends to the GND and Signal in on the RP6. I assumed it didn't matter which wire went which connection on the RP6. Any help would be greatly appreciated!

Why would you assume that?

Ground is ground and IR signal is IR signal.

If you do not know which lead is which you can use a multimeter to do a simple diode test on the emitter to figure it out.

Your application and alot more detail would yeild more help.

Are you trying to issue RTI trigger codes?

Yes the plan is to issue IR codes from my CQC controlled server. I am using both touchscreens (attached to CQC) and a RP6 for hard button remotes. The control through the RP6 has worked one hundred percent so far, so I am looking to take advantage of the reliability.

At first I figured that one was IR and one was ground, but I could not once find any reference on which wire was which. So I made the wrong assumption. Now in order to test the diode to determine which one, I use a multimeter and set it to ohms. This is where I get a little confused as I am not sure what I am looking for. I am assuming that I am trying to get the ground attached to the -'ve (anode) and the +'ve (cathode) attached to the IR Signal. What type of reading should I expect?

Thanks for your help, I am very knew to trying anything that doesn't involve straight plug and play.

It may be difficult to use a resistance test unless your meter can read mega-ohms.

If it can then...

If your polarity is incorrect you should get no reading. If your polarity is correct it may read in the 16-17 mega-ohm range (at least true for a Niles emitter)

A multimeter diode test uses DC voltage usually in the range of 1 volt to test this. Again, the incorrect polarity will yeild nothing while the correct polarity will show in the range of 1 volt.

Just an FYI... a simple continuity test is not valid for this kind of test.

Also... what is the DC voltage used for your UIRT? RTI uses 12 volts like most IR systems. You may have issues if it is a 5 volt system. If there is a compatibility issue, you can use a 12 volt receiver into the RP6 and stick an emitter on it from the UIRT. Not very glamorous I am afraid.

It appears the USB-UIRT is 5v and the RP6 is 12V. There was a solution that used to exist which had some sort of diode in between which would prevent the voltage from leaving the rp6 onto the USB UIRT but it appears discontinued. I may have to use a 12V receiver, and just hide all the mess.

You can always add your own diodes on both the signal and ground paths but I am not sure how the voltage differential will effect the system. I have never tried mixing voltages on an IR system and my first though would be just don't.

I will just take your advice then. The discontinued smarthome product would have worked perfectly, but that is life.

I think you refer to the Smartlinc P/N 1160: it uses an opto-coupled isolator

Smarthome # 8175

I have a few extras: email me if you need one: bought them a few months ago...sometimes they show in stock

Doesn't the PC to IR unit use those as well or is that a Smart Homes product as well?

Get out your video camera or your phone camera and look at the LED. When it blinks white, you have it connected properly.


Measuring diodes with ohmmeters can give you 100% wrong answers.

EVERY VOM and DVM I've ever used applies a positive voltage to the ground lead when measuring resistance, with the red lead being ground. If you're measuring resistance to see which lead you should attach the hot to, the ohmmeter will tell you wrong if yours does that. Check by measuring the voltage for the ohms test with a second meter set to Voltage. Don't be weirded out by voltage values unrelated to the battery voltages inside the ohmmeter; the range of the meter you're testing and the load resistance of the voltmeter will affect the measured voltage. You're just looking for polarity.


The way to determine the polarity of the wires on an LED is to sacrifice one. Did this even come up? Somehow I think it did....

Note how the wire is made so that you can feel or see a difference between one conductor and another by a ridge or a stripe. Lacking that, sometimes one inner wire is tinned and the other is bare copper.

Cut the wire apart at least a few inches from the plug. Strip both wires. Measure resistance from the wires to the tip of the plug: the one that shorts to the tip is the hot or signal, and when IR signal comes out, its voltage goes up from ground. Check the other one to be sure you haven't made a mistake; that one is the ground.


Incidentally, it could be easier than that: look for zero resistance between the power in minus connection and the LED out jack. If you can reach it.

Mark,

That would be great if you could sell me one. Please email me at

bauer83 AT hotmail.com, and we can arrange something.

Thanks everyone!

you have mail!