EEVblog Electronics Community Forum
Electronics => Repair => Topic started by: jtu on March 26, 2018, 09:43:54 am
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Hi,
I've got my hands on Hunting trail camera HC-300/HC-300M. It was stated that camera might have gotten wet.
Yes, there were signs of water inside, but minor. I have fixed the rest, working condition now, except camera does not recognise SIM card.
First, I can't google schematic... Aparently this is a cheap chinese clone, I really wonder why no schematic out there.
Second, any hints on how to debug a SIM? Card works in another device.
Veiksmi,
J?nis
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Any chance you could attach some reasonably sized photos? For whatever reason, those two are tiiiiiiiny...
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Thanks for noticing. And sorry, I have not learned how to resize pics for the forum easily yet. My mac offers some options, but I have not found a consistent one. There are web services, but those are slow and inconvenient.
Here you are, nevertheless. I'll add more teardown pics later.
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Yeah, if it has SIM issues, photos of (only) the outside won't help all that much, i'm afraid :)
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Here (https://photos.app.goo.gl/CQCQTjEZVEr2LtJ72) is link to the album. You can see main board from both sides, display board, sensors board there.
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Suspect the card holder but check the traces to it for any signs of data. Hopefully the controller hasn't been damaged.
More IPA cleaning around the card holder ?
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SIM card holder was prime suspect. Sorry, I forgot to mention that I re-soldered the holder. Cleaning included.
Ok, googled SIM pinouts, SIM holder pinouts. I was not able to find any SIM holder pinout similar to this case.
I tried to poke it with scope anyway. My findings: there is activity starting couple soconds after turning DUT on, high appears to be 1.8V:
pin 1 = ground
pin 2 = Vcc? gets up first, stays high
pin 3 = ground
pin 4 = I don't know, gets up last, stays high
pin 5 = seem NC
pin 6 = should be clock ~3MHz; it does the clock thing for ~3-4 seconds then goes low
pin 7 = should be data line; does something while clock is on, then stays high
To understand the sequence of the events I did it in pairs also: pin 2 gets up first, then 7, then 6, then 4.
I did SIM holder pic and scope screenshots, see gallery.
I should capture the whole thing probably to understand the ending. But for that I need to do some reading first, I'm not that proficient with scope yet :)
Any feedback appreciated!
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Nice scope ! :)
Yeah I have no idea of SIM card protocols or pinouts either, but you are getting something on the scope, great.
Thoughts....
Damaged card holder, dry solder joint ?
Try another SIM.
Good work. :)
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Hi guys,
I have a very similar problem with water resistance. But the humidity damaged (it started burning when I reconnected it) the cable that connects battery to the camera.
Any thoughts where could I get this kind of cable?