The Junkdrawer

Failed, discontinued or finished projects that turned out to being a bad idea in the end. Only stuff that got at least partially build goes in here. Some stuff I stopped doing simply because I found out somebody else did it better already.

A lot of the truly bad 2am ideas thankfully never got this far.

Source: Totally Absurd Inventions

The Timetraveling Radio

The Idea:

Get an old valve Radio from the 50ies and replace its innards with modern stuff. Put an Arduino and a Raspberry Pi in there. Put the charts from the 1920ies until today on it and set it up that you can tune it to different years.

How Far it got:

Got a radio, removed old crappy WTF-tronics (but kept the valves), added a PSU. Made a prototype interfaceboard for a rpi. Tested the whole thing witha small amp.

Why it was a bad idea:

• all the music from before 1965 is either horrible, annoying or both.
• most of the music from 1965 and after is either horrible, annoying or both.
• 70 year old mechanical electrical switches need higher voltages to work reliably even if you clean the contacts.
• the dials use variable capacitors I had no idea how to interface with at the time.
• the rpi (1) had a shitty noisy analog audio.

Lets upgrade my Desk with LEDs

The Idea:

add a “cool” looking grid of RGB leds to my new then Ikea glass desk. Have it signal incoming notifications and emails and do cool color effects. It could serve as indirect lighting at night.

How Far it got: It was basically done.

• hardware based on an early WSxxxx LED Strip was 100% done.
• including a spiffy slider-lock that clamped it in place I was very proud of
• software that let me send png files to it via USB from my PC.

Why it was a bad idea:

• a light up table shows every single goddamn spec of dirt.
• a light-up glass table is bloody distracting at night
• the desk is always filled with crap blocking the view
• I don’t care that much about notifications

Lets build a TES device

The Idea:

Zapping your brain with current looks fun and interesting - what could go wrong?

How Far it got:

bough most of the parts and something to mount it on. A Styrofoam Hemisphere makes one Look like a member of the Pet Shop Boys as a Bonus.

Why I gave up on it:

• death, fear of

Lets build a Spider Robot using meccano

The Idea:

Build a Spider Robot using cheap analog servos and even cheaper off-brand Meccano from amazon. This was before I had a 3D printer.

How Far it got:

Bought servos and Meccano; build the frame and mounted 6 Servos for the leg joints.

Why I gave up on it:

• Meccano is surprisingly heavy - too heavy sadly to make a legged robot like this from with cheap servos.
• very cheap analog servos jitter a lot if you half-ass the controlling electronics.
• Its hard impossible to attach meccano to a servo without a custom mount bracket.

Lets build an active EEG electrode

The Idea:

Texas Instruments had a spiffy new biomonitoring chip that amplifies bio-electrical signals (up to 8! per chip) on one side and spits out SPI on the other. Why not build a cheap active electrode based on it - make it wireless and solar powered, too.

How Far it got:

Sampled the chip - Ti send 1 chip <3. I made a PCB design for it and ordered the passive components. Homemade some PCBs.

Why I gave up on it:

• the chip had too small a package size - I was unable to etch a PCB with traces for it that would have worked.
• Ti only send me 1 chip so I had only 1 try - replacements were unobtainium at the time for me - unless I needed 1000.
• I leaned that energy harvesting from Solar indoors returns pitiful amounts of power