I noticed there is a black cable with what looks like a headphone jack on one end
and a black receiver?? on the other end included in the box with the Gateway.
Does anyone know what this is for?
According to this, Specs - Gateway Whole Home HDPVR - Shaw.ca it's an "IR receiver with tether". http://www.shaw.ca/gateway/specs/
But according to this Hardware Information - Portal / Gateway, it's not a "receiver" but "blaster".
"IR Tether: No - Port is an IR Blaster (output, not input) "
I don't use it but I believe it's just a signal "extender".
That would be an IR extension cable. The current generation of Gateway Portals support these and they come included, so you can use this to put your Portal in a cabinet, for example, and run the extender out from this so that it can receive commands from the remote control still.
Hope this helps,
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