You are reading content from Scuttlebutt
@dangerousbeans

MagUnsafe adapter

DL6T97AVQAAmCCL.jpg

This takes 12v and pushes it up or down to whatever voltage you'd rather have, like 19v to directly charge my mac. Doesn't really get warm compared to a mains charger, but does make some whining noises when you do anything on the computer, like a window scrolling makes a slight vvvffff noise

@mix
Voted this
@mmckegg
Voted this
@Ds

Nice one
I had one original charger that also did a noise while scrolling, plus....yours is prettier :)

@Ds
Voted this
@elavoie
Voted this
@meff

What chip are you using to step down?

@neftaly

Coil whine! I remember reading that you could use stats on those power fluctuations as a keylogger.

@Dominic

@neftaly maybe we could detect that at a distance using some sort of directed antenna?

@dangerousbeans

@meff it's this one: https://www.aliexpress.com/store/product/400W-10A-Digital-Controlled-Constant-Voltage-Current-DC-Boost-Converter/2918045_32800692736.html

$14.54 USD

@cel
Voted this
@interfect
Voted this
@miked
Voted this
@testdude2
Voted this
@cryptix
Voted this
@duncan

thinkunsafe.jpg

thinkunsafe_2.png

Thanks @dangerousbeans for showing me how to make these! ThinkUnsafe :sun_with_face: :zap: :computer: is now operational.

@duncan
Voted this
@juul

@neftaly yes. and the same with the normal EM from the computer. and from the monitor. and the noises from pressing the keyboard. and the reflection of the screen off your eyeball. and the LEDs on your network adapter.

@Sam Smith
Voted this
@dangerousbeans

@duncan looks good, please don't try to take this on an aircraft tho

@Nonlinear
Voted this
@duncan

MagUnsafe encounter #1

voltmeter.jpg

“I would never lie to you…”

Woke up this morning and switched on the boat’s power supply. Laptop was lying on the bench plugged in to the MagUnsafe from charging earlier. The headphone jack also happened to be plugged in to the stereo.

Heard a sharp buzz through the stereo, followed by a pop, then silence. Glance over at the laptop which was previously on and is now mysteriously off. Black screen, no lights, no signs of life when pressing the power button. Thought to myself huh, I guess this is the part where I toasted the motherboard. Good to finally know what that feels like.

The MagUnsafe has a built in voltage display which is very reassuring when it hovers right on 20 volts, ideal for laptop charging. Also there are some LEDs which change color as the voltage stabilizes a few seconds after connecting the power supply.

I had thought that’s great, this magical box is totally monitoring the voltage and probably keeps the laptop circuit disconnected until everything is ready. Well haha the joke’s on me because actually it’s connected the whole time, including an initial spike up to 30 volts.

What’s better is that the spike is hidden on the display because it starts in voltage select mode, and only goes into voltage readout mode when you press the OK button. So you might not know unless you connected a multimeter, which I later did:

voltage_chart.png

Anyway this raises a bunch of electrical engineering 101 questions for me, like does the spike even happen if a laptop is connected, and maybe there is a mode where it would be kind enough to not do that.

Laptop came back to life after disconnecting both the external and internal batteries for a while, perhaps it just went into a protective coma for a little snooze, or perhaps it will be scarred for life.

So gg MagUnsafe/ThinkUnsafe, proud of you with 2 from 2 attempted motherboard toastings. One of these days you will get me but that day is not today!

Join Scuttlebutt now