BTW, would you mind sharing what LCR values you got for your antenna and the existing one? I’d love to know!
Well, yes, but to clarify what I meant, the change will be linear with no frequency component, so although altered in actual impedance it would be evenly affected across the frequency range
As for LCR values, I think I’m close to the stock one, I only have a cheap meter but if I get time will dig it out and measure - haven’t got the figures to hand, it was all back of the envelope and not properly documented. Being a one off I documented process not specifics
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I’m sure I’m a little too late here, but a little trick if you don’t have exactly the right resistor is to use 2 in parallel, it will cut the resistance in half. You can do the math on it too and use different ones in series/parallel to make unusual resistance values, but that’s not as fun as just mix and matching random resistors up in series/parallel.
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I love this. I salvage a TON of parts from old electronics and SMD components are often overlooked
Such a goldmine or little odds and ends to make your projects work
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How long was the rod that you ended up using? I am going to try and make this to hopefully read by possibly dead NExT as a last ditch effort.
@Compgeek top post has some great info, if you were going to try this
and this may come in handy also 
(@pulsarforce is @compgeek brother, who also made a homebrew antenna)
@PeachSqueezer made a different version also, so he may be able to give you some pointers also.
I read the 9mm as the diameter, I meant the length they ended up cutting it to.
25 to 35mm. It is in one of the posts mentioned above.
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I ended up somewhere around 40mm, my first attempt at 25ish was too short.
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Resurrecting. Does anyone have a good source for ferrite rods in the US? Also, what’s the ferrite mix that you all used?
Batteries. Afghans just burn them then pull the carbon rods out. Don’t know if it’s the same but…… worth a shot haha.
I ended up buying mine from Digikey.
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Thanks! This got me to where I needed to be.
I xref’ed the mix 78 available with Fair-Rite’s listing.
From their site Mix 78 is best for “power applications for frequencies up to 200 kHz and low loss inductive applications to 500 kHz.”
They even specifically mention RFID rods.
Ordered a couple.
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Thinking about giving this a go …
How would 8mm or 10mm ferrite core do compare to the 9mm (8 & 10 are much more available than the 9 to me)?
1/2in (12.7mm) seam to be common here too, but that seem big …
Huhhh???
We might need to reboot Pilgrimsmaster, and/or defrag his harddrive.
Glitchy AI today,
Wargames tomorrow.
“How about a nice game of chess?”
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What proxmark do you have? Any way you could measure the resistance of it’s stock coil or count the turns and dimensions?