Every new dht11 i can find throw checksum errors

Other Hardware Sensors
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I've setup an Uno and a Mega that run a couple of dht11 sensors and some light sensors. they've been running fine for a couple years now. at the time i was able to find a 5-pack of dht11 sensors that work. (they say dht11 [followed by some kanji] on the back and have a red led on the front)

i'd like to setup some more dht11 sensors around my house but i've now ordered two 5-packs they both ended up having the same deign on the back (solid square with two pin holes on either side and three lines going from the box to a row of three more pin holes and a circle around the box... the box looks like it's metal)

so plug in old dht11 and it works. swap out for new one and it's checksum errors. (maybe sporadically working and mostly throwing errors... and i think it was checksum errors.... it's actually been months if not over a year since i got the first batch and tested with a dev arduino.... and today i just swapped out one from the second branch with a working dht11 and it's currently showing up as a checksum error in the database on a different raspberry pi than the one running it's arduino... so for all i know it is still sporadically sending data)

i'm more convinced that the dht11s i'm able to find anymore are all just garbage.... i have a couple extra unos and an extra mega i can test on. i'm just not really sure how to go about debugging this at this point. is it possible that these new dht11s need a newer version of the dht11 lib? how would i even go about doing that? i'm pretty sure i tried updating libraries before if that's something you can do in the Arduino IDE.... (again... it's kinda been a year since i've actually opened that up... i'd also had issues where i had a working motion sensor i got with a kit... and then when i got a pack of them i swear i was able to just swap in one of the new ones at it was working but then when i tried to update the code to use more than one motion sensor none of the new ones ever worked ever again.... and so i'm kinda struggling to get myself back into working on Arduino projects.... i'm afraid the new motion sensors i got from adafruit are gonna be bunk too...)

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Please post a link to where you got the latest sensors

3

That's...pretty novel

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i believe i got the latest sensors off of Amazon. i don't know if this is the exact item i ordered.... it was a several many months back... but they look exactly like this... (i wanna say that they listing for the second batch didn't include a photo of the back because i was specifically looking to avoid getting more like this)

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I don't see an LED on the items that you linked to. Can you take photographs of the front and back of the actual items that you have and copy them here ?

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yeah i'm assuming it's the manufacture's name or something like that.... i think i might have gotten them from a ebay seller out of china. and i've had other working dht11 sensors that came from kits that have different board designs. it's more that the last two packs i've got ended up having the same distinctive design. and that when i was specifically trying to avoid getting more of that design the last pack i got ended up being the same and also having issues...

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yeah these ones don't have an LED... the ones that i got years ago that do work have an LED

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