People have made half-duplex, 2-way single-fiber links this way.
With reverse-biased diodes, you are operating in photoconduction mode. If tightly-coupled to a fiber optic, and with a quantum efficiency of say, 10%, that would mean for every 10 photons which come in, you get 1 electron charge of current flow.
IIRC there are people who paint e.g. 1N4444 diodes with black paint to minimize opto-induced leakage.
You might also want to watch this video that demonstrates a 2D proximity sensor using an LED array. It works without a laser pointer, using the fingertips alone is good enough for it:
A few days ago, a user here also commented on how LEDs work both ways and how he used this effect to automatically adjust the brightness of an LED to ambient light. You can find that comment here:
...okay, but could this actually work? I'm assuming because there are no products like this that there's a giant caveat somewhere, but isn't it actually a good idea?
My understanding is heat pumps can move more heat energy in/out of a system than the electrical energy input into them. My peabrain logic thinks, "Wait a moment, doesn't that mean a heatpump oven would be more energy efficient than a conventional electric oven with resistive heating?"
I'm assuming the problem lies somewhere in refrigerants not, uh, behaving well at oven temperatures?
You will be able to reach small ~100°C heating before everything starts failing and getting on fire, then you will get much larger temperatures, once. If you have a bad enough circuit breaker, you may even reach metallurgic oven temperatures for a short while!
The refrigerant gas failing isn't actually a problem for high temperatures. They are a problem to getting too cold, but if you get hot enough, anything will work. Even if it burns down inside your pipes, the results will still work (but your pipes won't).
Ok, the question is if you could build an oven heated by a heat pump? Yes, you could.
You can reach home cooking temperatures reasonably easily, and probably even large ones. It's helpful that the compressor only has to deal with gases after they got cooled and heated again on the open air, all the really hot parts are rigid tubing.
There will be problems turning the compressor off, dealing with the heat that propagates back through the pipes. You can solve them with some usual cooling devices (heat disipators, fans, etc).
It has a way to push heat into it, some heat insulation, a door, and it's food-ready. The thing is basically an oven already, and 270K and 400K are just some 30% change.
I see they did a trick in the code: Because binary literals were added late in C++14, it seems they used some library which defined 256 constants like B00000000 = 0, B00000001 = 1, ..., B11111111 = 255.
17 comments
[ 3.4 ms ] story [ 51.5 ms ] threadWith reverse-biased diodes, you are operating in photoconduction mode. If tightly-coupled to a fiber optic, and with a quantum efficiency of say, 10%, that would mean for every 10 photons which come in, you get 1 electron charge of current flow.
IIRC there are people who paint e.g. 1N4444 diodes with black paint to minimize opto-induced leakage.
https://cs.nyu.edu/~jhan/ledtouch/index.html
A few days ago, a user here also commented on how LEDs work both ways and how he used this effect to automatically adjust the brightness of an LED to ambient light. You can find that comment here:
https://news.ycombinator.com/item?id=28475474
“…and in my next video I’ll show you how to bake a pizza in your freezer.”
My understanding is heat pumps can move more heat energy in/out of a system than the electrical energy input into them. My peabrain logic thinks, "Wait a moment, doesn't that mean a heatpump oven would be more energy efficient than a conventional electric oven with resistive heating?"
I'm assuming the problem lies somewhere in refrigerants not, uh, behaving well at oven temperatures?
The refrigerant gas failing isn't actually a problem for high temperatures. They are a problem to getting too cold, but if you get hot enough, anything will work. Even if it burns down inside your pipes, the results will still work (but your pipes won't).
You can reach home cooking temperatures reasonably easily, and probably even large ones. It's helpful that the compressor only has to deal with gases after they got cooled and heated again on the open air, all the really hot parts are rigid tubing.
There will be problems turning the compressor off, dealing with the heat that propagates back through the pipes. You can solve them with some usual cooling devices (heat disipators, fans, etc).
[1] https://www.arduino.cc/en/Reference/PortManipulation
https://www.youtube.com/watch?v=u_K1URyarE0