Odds are definitely very very low that both his cards are defective, but I’ve seen crazier things happen in my field of work. If he puts the diagnostic card on the lock then reads a tag through it, and let’s say it works and opens the lock, the diagnostic card should at the very least flicker right? It would be receiving more power than the tag at that point and the tag read/lock open would confirm that the coil activated at its fullest power.
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Well according to the em4100 data sheet it’s min voltage is 0.3v… the green led likely requires more than that so I am leaning towards this
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Well… That’s not promising.
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So what would the voltage need to be ideally?
.8v usually upto about 1.2v would be good for the LED.
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Well we are talking about voltage enduced in the tag. Not sure what the t5577 needs but the issue is more to do with antenna coupling.
For example in prototyping the HF LED Power Bracelet I can easily light the HF led on the diagnostic card at 5v (the lowest I have tried) I pass up to 30v to the same circuit to get a decently bright light out of the xLED unless I get the coil design just right.
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Oh I was talking about minimums 
as in the forward voltage of the led 
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I saw you had taken that possible answers. I took the other 
since the question had some ambiguity.
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When I have just into these situations many times.
Most recently with Hornaday Bedside Gunsafe and the Vehicle safe.
The Bedside safe works awesome. 1 in away boom drawer slides out and Daddys got his Pew-Pew.
The vehicle safe. Looks of similar design. You would think it would function the same…no.
I contacted them. At first support gave the…they are the same reader. Your doing it wrong.
Then I looked at the info provided by FCC. The crap they have listed is flicking incredible. Literally they have a teardown of the entire unit. The testing. The schematics, pictures of the antennas.
They even list the engineers who register them and there direct contact info.
I asked support to ask Matt why they used garbage v1.00a designs and low end reader components then market a 3 year old device with a brand new one.
The bed safe is a complete rework.
I then introduced them to Dangerous things.
They are thrilled! I told him get some samples from them. Fix your garbage to work. Then see if there is a possible partnership.
As a firm believer in protecting my family the last thing I want to do is look for some fob my cats could have knower under the bed so I can get my gun. Same in my car.(Maserati…i live in the hood. Need to be prepared)
So long story short. Don’t forget me if you guys partnerup. They are a big deal 
Second search for the FCC id for any product before buying to see the guts of it so you know if garbage will work with enhanced thinking
I’ll try to post links later
I just want to reach for it…and it works.
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I always love the fcc teardowns there so useful!
Also I’m never not amazed by how most people react to implants and dangerous things (the company) really is a positive.
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So I had an idea of be a way to make it work but I wanted to run it by you guys first say I were to take the copper wiring out of the doorknob instead of making an internal coil making it external coil do you think I could possibly get enough current off of it by making it to where I almost touch the copper wiring with no casing
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That would definitely increase the odds if it is a coupling issue but no guarantees.
Can you take a few photos for us, with the cover plate off, specifically where the antenna lies?
This is first look after taking the back panel off of the door knob looks like there’s a secondary board under this top one just wanted to give you guys an update I’ll send another photo once I get this main
board off
Edit: I will also be in DTs discord if you would like to join
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Interesting it seems to only activate fully when jostled or moved
Also ignore the raging in the background my roommate’s learning how to play Rust
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That video is actually quite helpful.
Can you do me a favour and just leave it lying on there ( and or the Diagnostic card ) for about 10-15 secs without moving it?
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I did that and got nothing from the diagnostics card but very dim flashes from the field detector
Where are you finding this? Links? That’s amazing.
My email address is just my name at dangerousthings.com… send an into? I’ll make sure they get samples.
I noticed the same behavior on a quicksafe hidden wall vent safe I have… probably a battery saver method that’s actually quite brilliant… if you know you have to smack the thing to wake it up. If not, you might think it’s a shitty inconsistent unit.
You definitely have to smack it to get it to wake up from my testing yesterday that I didn’t include the video I tried setting it gently on to the coil and got nothing but the small almost invisible light flashes you could see in the video wonder if I could find somebody who could help me up the voltage without frying the board
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