Re: Slink-e powers off

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I was using US phone leads - hence the problem. Now it seems that I've 'blown' two of the IR

Transmitters - does this sound possible? If so, which IR LED would you suggest using when

constructing a replacement?
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Since LEDs conduct only in one direction and there is a current limiting resistor, I would find it suprising that they would be damaged by mis-wiring. In fact if you use a phone style cable, you would have connected the tx module to ground and the receiver input - hardly a dangerous combination (the rx module, however, would have its 9V and GND reversed which is not good).

Since you are in the U.K. and are using your own AC adapter, my guess might be that the DC voltage coming into the Slink-e might be too high, and so the current through the LEDs (which run from this unreg supply) was excessive. The LEDs are a Lite-On LT1062 rated at 150mA continuous and 3A peak. Assuming a 9VDC supply, you would get about (9(supply)-5(leds)*1.3(Vf)-0.2(Vcesat))/10ohms = 230mA when the LEDs are turned on. If you had a very high current unregulated supply, you might end up with something like 13VDC, in which case the current would be more like 530mA. With the 50% duty cycle carrier and short duration IR waveforms, the current should be within the limits. Did you apply a continuous voltage during your testing? This might have done them in. You can basically choose whatever LEDs you like, as long as you observe the current ratings and choose the appropriate current limiting resistors. The LT1062s are particularly powerful, which is why I chose them. I'd try to do some other tests without the Slink-e first to make sure the LEDs aren't working - just watch out for over current!