DCAWD.com

USB gadgets usually don't impress me considering almost all of them involve a fan ... this one stuck out to me though.

USB Popcorn

That might be a real video, but something has been changed or doctored. If he is using USB 2.0, then he could get up to 5 loads on the single port, but since there is no device to authenticate or handshake with, the port will default to one low power load. To get more than that, he would have had to write a special driver and assign an identifier for his "device". If that is the case then I guess he could max out the hub and get the full 5V .5A.

He is over-driving the halogen bulbs, so they should be getting really hot, since it is in low power mode, the max he is going to get is (5Vx0.1A) 0.5 Watt. So in about 20 mins he could the oil hot enough to start popping some kernels, but look at the container - metal? There just is not enough thermal insulation in that setup to keep the heat in to raise the temps enough.

zaxrex wrote:That might be a real video, but something has been changed or doctored. If he is using USB 2.0, then he could get up to 5 loads on the single port, but since there is no device to authenticate or handshake with, the port will default to one low power load. To get more than that, he would have had to write a special driver and assign an identifier for his "device". If that is the case then I guess he could max out the hub and get the full 5V .5A.

There are USB driver chips specialized for this - they send just enough data up to the Host device (laptop, pc, whatever) to get it into high power mode.

Still, that would get him up to a theoretical 0.6 cal/sec of output. In a closed system he could get 2 grams of oil hot enough in about 5 minutes. That is not taking into consideration any losses. That cup is going to be radiating most of that heat away.

I still don't see it happening.

I'm not questioning your thermodynamics, I'm just saying, I gotta chip that will make it do full output.