Sending a signal with Adafruit super-bright 5mm ir led 940nm

Hi! What firmware is on your Puck.js, and which version Puck is it?

This seems like something you should be able to do pretty easily and your code looks fine. Do you see anything appear on the second Puck if you paste in Puck.IR([1.3,0.4,1.3,0.4,0.4,1.2,1.3,0.4,1.3,0.4,0.5,1.2,0.4,1.2,0.4,1.2,0.5,1.2,1.3,0.4,0.5,1.2,0.5,7.9,1.3,0.4,1.3,0.4,0.5,1.2,1.3,0.4,1.3,0.4,0.4,1.2,0.5,1.2,0.5,1.2,0.5,1.2,1.3,0.4,0.4,1.2,0.5,7.9,1.3,0.4,1.3,0.4,0.5,1.2,1.3,0.4,1.3,0.4,0.4,1.2,0.5,1.2,0.5,1.2,0.4,1.2,1.3,0.4,0.4,1.2,0.5,7.9,1.3,0.4,1.3,0.4,0.5,1.2,1.3,0.4,1.3,0.4,0.4,1.2,0.5,1.2,0.5,1.2,0.4,1.2,1.3,0.4,0.4,1.2,0.5,7.8,1.3,0.4,1.3,0.4,0.5,1.2,1.3,0.4,1.3,0.4,0.5,1.2,0.5,1.2,0.4,1.2,0.5,1.2,1.3,0.4,0.4,1.2,0.5,7.9,1.3,0.4,1.3,0.4,0.4,1.3,1.3,0.4,1.3,0.4,0.5,1.2,0.4,1.3,0.4,1.2,0.4,1.3,1.2,0.4,0.4,1.3,0.4,7.9,1.3,0.4,1.3,0.4,0.4,1.3,1.3,0.4,1.3,0.4,0.4,1.2,0.4,1.3,0.4,1.2,0.4,1.2,1.3,0.4,0.4,1.2,0.4,7.9,1.3,0.4,1.3,0.4,0.4,1.3,1.3,0.4,1.3,0.4,0.5,1.2,0.4,1.3,0.4,1.2,0.4,1.3,1.3,0.4,0.5,1.2,0.4]) in the IDE?

Using an external IR LED should be fine though... You'll just have to specify the pins with Puck.IR(data, D30,D31) (and maybe swap D30/D31 if it doesn't work first time).

Or, the code that's in your HTML:

        // Start the 38kHz square wave
        analogWrite(A5,0.9,{freq:38000});
        // Send the pulses
        digitalPulse(A6, 1, times);
        // Wait until pulsing is finished
        digitalPulse(A6, 1, 0);

Should work fine too - you just have to change A5/A6 for D30/D31.