NFC antenna amplifier/Resonance Circuit project

Before you spend a bunch of money on flex (I recommend JLPCB for your first few flexes because they’re cheaper btw) we could voice chat in discord and I could go over some stuff with you. I’ll be around today. Otherwise I’ll just post a little guide here. Lmk what you prefer. I can also review your boards before you send them out pretty much whenever you need.

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That’s who I normally prefer to order all my boards from.

Today and tomorrow I’m booked through with Dad shit. I’ll msg you tho

I’ll try to put together a post about the onboard capacitor plate calculations today or tomorrow, but for now I can say the easiest way to make circular traces in most PCB software is to make squares and then round the corners with a radius value that is half the length of the trace

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I designed a similar PCB a while back: GitHub - StarGate01/rfid-breakout: Breakout board for a RFID MOB smartcard IC , if you leave out the chip it should function as a repeater just as well.

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Reading through your git it looks like you used the same generator I found on kicad forums to make the antenna. I’m gonna try to tweak it a bit to make it more circular but yeah design is almost identical

First set of pcbs came in.

Very happy with the way they turned out.

I also received my new Pixel 8 today so just in time to add these to my case.

Soldering went easy. Surprisingly enough is easier to hand solder these than to use the hot plate. Much easier to quickly create these. I also ordered a shit ton of boards because it was literally pennies more. If anyone wants one and is in the US I’ll send you one and I’ll cover shipping.

@Satur9 since I now have some more time, I’m going to look into maybe resurrecting the old idea of the antenna sticker. Let me redesign this circuit to be circular and I will reach out to you regarding the integrated capacitor.

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download (1) (4)

I looked for a xenophobic gif, but it only gave racist results, so that’ll do

:wink:

Awesome little project by the way

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I’ll ship them out to anyone that wants I have a ton

But you only get free shipping if you’re in the US.

Just dm me your address and I’ll figure something out

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i don’t do business with racists :wink:

I’m just joshing you.

However
If you do send any to Amal, if you send him an extra one or 2, I’ll ask Amal to include it in my next order.

That’s if hes happy to, but he’s not racist like some people I know :wink:

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Ill change it to US Residents and those currently living in our Hat (canada). Being in detroit my rates to canada are pretty good.

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Nice work! I’d love one or two! Did you buy the coil or did you make it yourself?

The coils are orphaned from old rfid tags. Shoot me your address in a dm and I’ll send a PCb out to you

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Quick Explaination of this PCB, and how i used it to tune some of these tiny NFC antennas for my use.

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I wish I had those when making your range extenders @invalid_signal :rofl: it would have made things easier and cleaner. Although you get the extra thickness of the pcb…

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Fr4 PCB isn’t that thick

But the flex… oh boy she is skinny

For those wondering that is 15x my Patience for my wife’s spending habits

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I didn’t realize these were flexes. That would have worked. I think @invalid_signal wnated to cast them in flexible phone cases.
Mine had the smd cap directly soldered to the wire

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Yeah that was what i did before but man, i think im just too old to try to be that steady with my soldering. I need like 30 helping hands now a days… Or, i just oder PCB’s slop on the solder paste and let the hotplate do the lifting

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These look cool! Nicely done!

I’m almost done moving into my new apartment. Hopefully I’ll be able to get my work station set up before the end of the month. Life’s just been so busy!

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I very much want one,
I can shoot you address, or if you ever want to meet up with a fellow troll for drinks or hang out

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shoot me your address… The second spawn has impacted my drinking significantly.

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