HF LED Power Accessories

The second one is what I was talking about. Out of curiosity, what kind of power source will this require?

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I am using a variable power supply on 5v ATM.

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A pair of Li-ion batterys in series would be ~7.4volts. With a voltage regulator 5v is easy. How long it would last depends entirely on the amps being comsumed.

With absolutely no disrespect to leuma95 this isnā€™t far enough along to be worrying about that just yet.

And, Dude.
Thatā€™s friggin awesome!

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I donā€™t plan to utilize a bracelet. My led is up on my forearm, so I would prefer throwing an antenna next to it under a tegaderm.

I see that in your graveyard,
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you havenā€™t yet tried this configurationā€¦
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JUST SAYING!
I hope that helps

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Problem

SOLVED

Youā€™re welcome

Geez Iā€™m helpful

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Those are almost tight enough! Figured I could swap put my forearm bones for iron. Boom, I can light the whole crowd up.

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Flat spiral coil works for the test card too, but not the X FD

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I gave it a go :stuck_out_tongue:

I swapped the capacitor from 32pf to a 2pf one so I could try a bigger coil.

Coil works for the diagnostic card but canā€™t get it to light the X FD.

3 inch coil, 27 turns, 18awg wire.

And I moved the implant all over the place, nothing worked. Powers the diagnostic card from all over the place.

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bugger, there goes the neck ring idea

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How dare you give up so easy.

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Easy? My fingers strongly object to you calling it easy. There soft and delicate after all the staying inside and hand washingā€¦

tenor-3

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@amal I feel like I have seen you talk about an HF version of the DT LF antenna for the RDV4. Would you know anyone who could point me in the right direction for a coil that couples well with the HF implants?

Edit: or simply the full specs of the coil in the xLED so I can try simulate it with some software.

I never said YOU were easyā€¦ but are you?

Seriously though, looking at what you did, makes me want to learn it now.

Haha.

Itā€™s quite fun, Iā€™m pushing my memory though. Havenā€™t worked with circuits like this for more than a decade.

I usually just hook up microcontrollers to things and then do all the logic in code.

ATM I have just cloned the circuit @Satur9 had drawn up

And Iā€™m tweaking the capacitor and coil inductance and shape, ensuring the resonant frequency stays at 13.56MHz.

But the shapes Iā€™m using are all vaugely informed guess work.

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images

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Well if you do actually want to get involved in this project or just hobbyist electronics Iā€™m sure plenty of people (including myself with my hodge podge knowledge) would be more than happy to help out :slight_smile:

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Excellent job with the testing @NiamhAstra!

The air core coil will light the LED in the center because the magnetic flux is densest there. The ferrite core coil is closer to what weā€™re going to want. You can check out my last couple posts in the tragus wireless headphone thread to get some more details and links. Basically, the variables that increase field strength (B) are:

  • Current flow
  • Number of turns / length of coil
  • Permeability of core material

So I think we can try two avenues

  1. Air-core bracelet with max turns in minimum length and larger amount of current.
    (That transistor can handle 40V so maybe we bump that up and run a few in parallel. Will require change to circuit)
  2. Try a different core material. Small coil (not bracelet)

I dunno, Iā€™ll have to get back to this later

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Really, I miss configured my variable power supply and over volted them a bit and let out the magic smoke. Although maybe that was overloading the gate.

My new variable power supply is weird it (at least on this circuit) always shows 0.0 A draw which seems wrong. Was going to test something else just to see if itā€™s like not broken and is just drawing under 0.1 A.

Iā€™ll have a look into your suggestions some time later today :smiley:

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I also grabbed some stuff to try make a 125MHz coil just to see if I have any luck with that.