Inductive Charging

[AtomSoft]

Found the section i think here:

**broken link removed**

 

[ronsimpson]

There is a frequency that the "dog fences" use. Almost the same thing. Inductive pickup, but the loop is a little larger. lol
There is a frequency for "wire locators". I believe it may be the same as above.
I built a project that used a hole at 455khz.

If you build just one........Maybe you should check what is happening at that frequency. Police band!
If you build 1000 you need to be right!

 

[AtomSoft]

hmm... how would i check these things? I know nothing on wireless

Can i simply make sure the range is under 1 foot ?

 

[ronsimpson]

I noticed there is a band 13.553 to 13.567mhz where you can have a large amount of radiation.

"(a) The field strength of any emissions within the band 13.553–13.567 MHz shall not exceed 15,848 microvolts/meter at 30 meters."

 

[dr pepper]

Heres an interesting circuit, with values.
Its for a toothbrush and charges baterries straight from the mains.
I did something like this way back, though it operated on 12v, it was a strobe for a boat and it charged itself via its stand inductively.
Dont hope for high effeciency, unless you spend a lot of time developing such devices waste more than they put out.

 

[dr pepper]

https://donklipstein.com/samschem.htm#schras4

 

[AtomSoft]

I cant wait to get paid this week and order some parts and goto radioshack for that magnet wire.. I think thinnest is better but it comes in a 3 size pack... ill be sure to get a couple packs... Ill also be sure to document it because i forget a lot of stuff i do

 

[Mr RB]

The toothbrush chargers work well as they usually have a metal cored former in the base which sticks up and goes inside the receiver coil, and quite short distances, some mm.

I really don't think it would be that hard, the main thing is the mechanical construction constraints and distances, and the amount of power you need to receive. If it's only a handful of mA it should be easy. If you need to fast charge a Li battery at 500mA that's a different thing!

 

[misterT]

I watched closely the development of this product. It was originally a school project and turned into a real business: **broken link removed**

I know It is a very simple device. It has a coil printed on a multilayer PCB and it can also transfer data (feedback data to the transmitter). I believe the new Nokia phones are compatible with their transmitter.

 

[KeepItSimpleStupid]

13.56 MHz is an industrial frequency. Some products include: **broken link removed**

I maintained a 1000W 13.56 MHz transmitter for an RF plasma deposition system (Sputtering). No license required.