Not as fancy as a lot of the projects here, but...

[SiliconWizard]

Nice.

I tried making Al-Air batteries at some point, as I thought there was great potential with them. They worked but not for long. That's pretty hard to avoid aluminum surface oxidation, which quickly makes the internal resistance rise.

If you coat the aluminium in activated carbon it stops it oxidizing. The Australian ultra-batteries, where they do the same thing to the lead plates in a lead acid battery, would be the source for a good glue/ink recipe. The carbon stops the lead plates oxidizing and producing gas, it should do the same to your aluminium electrodes, as well as increasing the surface area ten-fold, increasing the energy density.

Thanks for the tip. I'm still interested in metal-air batteries. Is that what you're referring to? https://www.csiro.au/en/Research/EF/Areas/Energy-storage/UltraBattery

[CM800]

I wonder how far you could go with making stuff using only household materials.

You're allowed one thing extra: A vacuum pump

I'm curious if someone could go far enough to make a valve radio or similar, even a simple amplifier.

[SiliconWizard]

[JS]

I wonder how far you could go with making stuff using only household materials.

You're allowed one thing extra: A vacuum pump

I'm curious if someone could go far enough to make a valve radio or similar, even a simple amplifier.

Pretty far, there are basement made vacuum tubes, given you need some tooling and materials but nothing way to special.

There was a story about a guy ho did so in times of war and got some mad dudes checking what was going on. I can't remember who it was...

JS

Enviado desde mi LG-M250 mediante Tapatalk

[VelOBor]

Nice!