BEN RITCHEY wrote in a message to ALL:

 BR> I am using one of those IDE to USB I/F cables (works great) 

Where'd you get it?  I think that this is probably just a bit more
complicated than being a "cable",  though.

 BR> and would like to add a remote LED "activity" light to the device.

What kind of a device?

 BR> Is there a pin on the 40-pin IDE cable that will accomplish this?

Not that I'm aware of.  There are often connections on HDs for an LED.

 BR> Should I use a simple transistor I/F (resistance coupled) to 
 BR> isolate the tap?

Assuming you do find some particular pin that would be useful for this
purpose you probably would want to give that signal some additional drive
capability with a transistor (or a logic gate buffer or similar).

I don't have a URL handy,  but there has to be a spec for the interface out
there somewhere that should give some useful details.

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