Software-defined radio and a steam engine built out of crap

Two quick things I’ll be getting to in a bit.  The first is an open-source software defined radio.  

The Gnu nerds have figured out how to hack a simple european usb tv tuning stick to make it work as a software-defined radio.  If you’re unfamiliar with what this is, it’s essentially a radio that scans and either decodes or stores all receivable radio frequencies simultaneously.  This particular model can also be reversed  and transmit in the same way.  
 It’s theoretically (and actually) possible to record a segment of radio reception for a certain amount of time, then go back to it and decode any and all frequencies you’d like, across whatever modulation methods  you’d like to use.
I picked up this usb stick  or $27 including shipping from a dude in Niagara Falls.  A quick ebay search for “nooelec” will help you find him.
If you buy anything be sure to ask him for a drawing.
My goal is to convert this software code so that it can run on a BeagleBone or Raspberry Pi microcontroller, making it the world’s first open-source standalone software defined radio.
I probably won’t get to that.
But I’ll be leaving SDR’s for a while until this whole solar thing gets sorted out.
I also built a steam engine out of crap parts and sticks I had knocking around.  It looks gross and it’s not quite done but ideally it should be able to torque a 12v stepper motor such that at least 600mA will be kicked out of it.
I’m also leaving this alone until the solar panel is done.
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The maths behind the sun powering my toaster while I bathe

Maths are a lot like karate.  It’s just cooler when an Asian is doing it.

But I needed to do some calculations or I wouldn’t have enough amperage to do anything useful.  Also I wanted to know just how the hell much this was going to cost.
First, I did want to calculate the amp hours that would be needed.  All of these calculations are done assuming 12v battery storage.
First, I’m going with the national average for household power consumption.  I know that I probably use more than this, but this will be the rough baseline.  The average consumption is 1000 watts at any given point in time.  So that’s 1kW/h.  At 12 volts and thanks to Ohm, storing 1kWh would require storing 83.3Ah.
83.3Ah * 24 hours = 2000Ah on the nose
As I’m only going to assume that I’ll have 5 hours of direct sunlight per day, I’ll need to come up with 2000Ah at a rate of 400A/h.
Incidentally that’s enough power to kill 20,000-40,000 people.  The collective State of Texas now has a boner.
I’m tired of going over this, it works out to me needing 400 square feet of grade A solar panels at a cost of $1700-$2400.  And a lot of  2 guage wire, which is somewhat impractical.  So small scale time, lets make around 80-100 watts.
The goal is to be able to generate 100 watts for $100.  
More to come…

My next attempt at accidental electrocution

We are like tenant farmers chopping down the fence around our house for fuel when we should be using Nature’s inexhaustible sources of energy — sun, wind and tide. … I’d put my money on the sun and solar energy. What a source of power! I hope we don’t have to wait until oil and coal run out before we tackle that.

– Thomas Edison (1931)

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I’m not a dirty hippie.  I use plenty of non-renewable energy sources.  But I’m not thrilled with it.  So for an exercise in mathematics, electronics, and chemistry I decided to see what it would take for me to be able to reduce my overall usage.

After the maths that resulted in me realizing that a 6m x 6m solar panel would be required to power my home I decided to not jump right in to a multi-thousand dollar investment.  But I did, after playing with a simple little 1.5W panel from Radio Shack, decide that piecemeal and proof of concept would be a more interesting way to go about this.  So let’s at least make a little juice.

I started by purchasing 36+ 4.54A 0.5V manufacturing grade cells from an eBay seller.  This came with bus wire, a junction box, flux, solder, the whole thing… for $48 with shipping and such.  The jobbers came in and I immediately tore into the situation.  What follows is the start.