[Jason] converted an Easy Bake Oven to USB. If you have to ask why you’ll never know.
Easy Bake Ovens have changed a lot since you burnt down your house by installing a 100 Watt light bulb inside one. Now, Easy Bake Ovens are [bigclive] material. It’s a piece of nichrome wire connected through a switch across mains power. Part of the nichrome wire is a resistor divider used to power a light. This light assembly is just a LED, some resistors, and a diode wired anti-parallel to the LED.
This is a device designed for 120 V, but [Jason] wanted it to run on USB-C. While there are USB-C chargers that will supply enough power for an Easy Bake Oven, the voltage is limited to 20V. Rather than step up the USB-C voltage, [Jason] added some nichrome wires to divide it into six equal segments, then wired all the segments in parallel. This lowers the voltage by one sixth and increases the current by a factor of six. Good enough.
The power supply used for this hack is the official Apple 87W deal, with a USB-C breakout board (available on Tindie, buy some stuff on Tindie. Superliminial advertising) an Arduino Uno connected to the I2C pins. A few bits of code later, and [Jason] had a lot of power coming over a USB cable.
With the Easy Bake Oven fully converted, [Jason] whipped up a batch of cookie mix. After about 15 minutes the cookies crisped up and started to look almost appetizing.
While the result is weird — who on Earth would ever want a USB-powered Easy Bake Oven — this is honestly a fantastic test of [Jason]’s USB-C PHY breakout board. What better way to test a USB-C than a big resistive load, and what better resistive load is there than an Easy Bake Oven? It’s brilliant and hilarious at the same time.
now add a raspi with wifi to notify you when the cookies are done…
…and you could bake a raspberry pie with your Raspberry Pi!
Well, you could wrap some pastry round a raspberry, maybe.
As a kid, my sister’s ran on a 12V car light bulb, I think maybe from an indicator. Off a great big brick of a transformer. It meant there were no dangerous voltages outside the sealed plastic brick, and it couldn’t generate enough heat to cause any proper burns.
On top of the bulb was a takeaway foil can, on a lever that flipped it into place over the bulb (which is under a grille). So it’s a teeny takeaway-sized area reflecting IR from a bulb into a teeny wee area, for making very small cakes.
I wondered before she got it, how it could possibly work, glad I do. Surprised the American one uses mains. Is it the official Hasbro (or whoever) model you / Jason are talking about here?
Also pretty sure you’ve gone wrong somewhere in your six-based maths explanation.
The reason why there are black and silver EasyBake Ovens. A 13 year old girl wanted to buy one for her 4 year old brother, but didn’t figure he’d like a pink and purple one. The story gained attention and Hasbro responded by introducing the black and silver version. https://www.washingtonpost.com/lifestyle/kidspost/protest-over-girly-easy-bake-ovens/2012/12/10/0eab1248-40a9-11e2-bca3-aadc9b7e29c5_story.html?noredirect=on&utm_term=.1c65045e1a6d
Small correction:
“This lowers the voltage by one sixth and increases the power by a factor of six.”
Should read :
“This lowers the voltage by one sixth and increases the current by a factor of six.”
The overall power stays the same, otherwise he’d be pulling 600W through a USB port!
No, running it on 20V from a USB plug is reducing the voltage. To 1/6 of what it was designed for. I won’t bother re-phrasing it properly, Jason does a good job of explaining on his page.
You won’t bother rephrasing it because you aren’t Brian Benchoff.
I read it as if the nichrome had been cut into six lengths that were then put in parallel. Before they were cut each length would have had 20 Volts across it (120V / 6) and now they have 19 Volts so it seems it is close to the same power and with the same current per segment but 6 times the total current as the segments are now in parallel.
Realistically though the length and resistance of nichrome changes as it expands with temperature. It has a positive temperature co-efficient (PTC). So I would expect the power consumption to be close to exactly the same.
For some reason I feel an urge to buy something off tindie…
(until I saw the shipping price)
Looks like a really handy breakout, I’d probably buy one if I could think of a use for it!
Now convert it to a reflow oven, and you’ll really have something!
Oh dear, Brian Benchoff strikes again. I’d have assumed you knew your way around fractions, with the foolish fanboying of SAE units &c., but I might have been mistaken. Lowering the voltage BY one sixth is not the same as lowering the voltage TO one sixth. This is just very sloppy writing. I hope you can do better.
Sure Brilliant Benchot can do better. Give him a box of HaD stickers, he will ACCURATELY hand them to anybody.
I was confused until I re-read the article and realised Brian had actually made a mistake. My head auto-corrected it to “to one sixth” from “by one sixth”.
Assume: “make and ASS of you and me”.
Seems you DON’T know your way around the English language.
This is just very sloppy writing. I hope you can do better in your next comment.
Reminds me of one of my favorite hacks, the USB powered griddle:
http://static.neatorama.com/images/2006-08/usb-bbq.jpg
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The embed didn’t work, no idea how to make that work. The link is there though.
The Flite Test crew used a similar technique to rewire a toaster to run from a 6S LiPo for their Flying Toaster plane: https://www.youtube.com/watch?v=i00thtWgvDs#t=1m45s
Wouldn’t higher current and the switching power supply make this less efficient than connecting to mains?
A bit. But then the point is it runs off USB-C. That’s the point, to draw a ludicrous, absolute maximum amount that the standard allows. And to put it to a use it wouldn’t usually.
WTF is “anti-parallel”?!
In parallel, but the opposite direction. So the LED faces with it’s anode one way. The diode is in parallel with the LED, but it’s anode faces the other way. Anti-parallel. Mostly a word you’ll see used about diodes. Also “inverse parallel”.
Actually the best example is probably a bi-colour LED. 2-pin LED housing containing a red and a green LED chip, connected together in anti-parallel. Depending on the polarity you connect it with, either colour will light. If you rapidly switch it’s polarity, you get yellow. Or orange with the right timing periods.
+1 for the [bigclive] reference – https://www.youtube.com/user/bigclivedotcom