This stuff is fascinating. I'd not heard of DCRS until a good friend pointed me at a YouTube video, this one:
[youtube]R6UCwqjdpo0[/youtube]
So, Dipole Coil Resonant System eh, lovely jubbly. I decided to partially replicate it, as a home made simple version and run it on 1.5V
Here's my vid:
[youtube]veYKg25X5Uw[/youtube]
1.5V and using 20mA. A tiny system, but allowing a lot of room for tunings and to move to higher voltages if wished further on.
Specs of the transmitter side: Transistor - MPSA18 Cap - '101' ceramic Resistor - 7.1K (1x5K, 1x2.2K whose tolerances gave 7.1K total) Ferrite rod with 17 turns one side, center tap, 18 turns on the other of approx 32AWG.
Receive side: 0-512pF variable capacitor 4x 1N4148 diodes 10uF electrolytic capacitor Ferrite rod with original factory radio windings in place.
A summary would be that it works well and is very simple to build. A test LED on a round ferrite choke showed that the best outputs come, marginally, from 1 side of the ferrite. Different coils have been tried and i'll include pics of those at some point in the near future. Best performing so far, has been a comparitively large half semi circle of ferrite from the tube of a CRT monitor, with approx 20AWG wire in the now familiar 17+18 turns arrangement. Inductive range of that coil has been a measured 3.5" with a red LED on the receiving section. That comapres with an average 2" until a marked fade off of LED glow. A stock standard radio ferrite with its original windings has been tried and does work, though with a much reduced output. All very rudimentary so far.
Whether the Korean guys intended for the turns to be asymmetrical isn't known. On my own variant, the slight spacing of their turns has less output than a closer coupling of all turns being tight side by side.
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ʎɐqǝ from pɹɐoqʎǝʞ a ʎnq ɹǝʌǝu
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