Improved - Simple Wireless Electricity System - SWES 2

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The original Simple Wireless Electricity System set of 3 videos were posted in October 2012.
Since that time, a few people have asked for help with their non running systems. So, I decided to have another look at it and hopefully simplify further, while also improving the performance. It's always been intended as a starter system, for newbies and tinkerers who have become interested in wireless electricity.
Adding a diode from the positive of the battery, or a resistor to the negative rail, or a pot to the Base and caps to the coils are for other systems...SWES just uses a transistor !
This thread will detail where i'm up to and any interesting tests, etc.

Here is the vid uploaded today of SWES 2, the improved version:

Wider operating range of voltages: 0.6V to 3.6V (original over saturated the bifilar coil above 1.5V)
Easier coil construction
More efficient current usage (20mA to 40mA typically, compared to 10-20mA higher on the original bifilar pancake system)

Added features -
Works well as a transistor tester
Easily enables transistor leg identification and whether NPN or PNP
Works great on a 1.6V 'calculator' solar panel sat near a table lamp.



Extras to the video include 1 wire transmission. By connecting a wire to the Collector transistor leg and with an AV plug made of 2 diodes on the end of the wire, an LED will light to several feet of distance as tested so far.
Battery charging is enabled by using a diode in series with 1 wire from a receiver coil.
If clip leads are used to connect the circuit battery and a loop is made in one of those leads, a receiver coil will pick up wireless energy - see pic below.

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YouTube user superMindstorms made a comment about running a microcontroller.
Interesting to note that the poor fella was having troubles getting a SWES to run until I uploaded this one and now is already thinking bigger lol

Previous testing with the SWES and tests today give good confidence in that ability.
Left to free fill sat on top of a SWES 2 transmitting coil powered by a 1.5V AA, a receiver, diode and capacitor can top out at 27.5V. 
While a FWBR, cap and 7805 would be ideal, the idea is to keep this very simple and yet safe.

Here's my response, because it does bring in that highly usable functionality:

superMindstorms
1 hour ago
Linked comment

Is there an way to transmit 5v to power an microcontroller?
Reply
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slider2732
2 seconds ago

Yes, not terribly difficult, but does need a meter to check the output for voltage and current. First thing is to put a diode on 1 wire of the receiver coil, then a capacitor of say 100uF across the other wire and the diode end...you'll need the smoothing anyway. Check the level the capacitor reaches at different heights from the transmitting coil.
On the system in the video, a 470uF cap reached 20V in under 1 minute !
The microcontroller circuit will draw down that voltage, but, safest thing is to put a 7805 voltage regulator on the output from the capacitor and then your sweet spot range will increase and the microcontroller won't get fried 

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A good tip for current limiting to small devices such as digital watches was found today.
Instead of using a diode to set up a pos/neg feed on the receiver coil, use an LED.
Now, the receiver coil will have an LED, then a smoothing cap across the LED output and other coil wire (10-100uF typically) and the watch circuit connects to the cap.
Doing so brightens the LED as the coil moves nearer to the transmitting coil, with the result that the watch circuit stays happy with its power input over a much broader range of induction distance. The LED brightens or dims instead of the probably sensitive circuit being affected.

The standard SWES 2 in the above video has a 1.5V induction range of 1.5" for a red LED.
Adding a '103' 0.01uF ceramic cap over a 6.8K resistance, between the Base and transmitter coil, moves that up to 2.4"
Just a note...as it's not intended to be morphing into such a circuit.

Being able to run from 0.6V, i've tongue in cheek decided to call it "The Wireless Joule Thief"