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I have an old castaway PCB that was being thrown out. I am having a hard time figuring out where all the traces go.

Could a dental X-ray device be used to scan it (thus making it easier to follow the traces?) I am not worried about getting permission (I have not advanced to that stage yet,) I just want to know the possibility of doing so (and what risks I am taking towards the X-ray device.)

JRE
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BarrowWight
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  • What kind of dental X-ray machine tho? The one with the very long arm? – Bradman175 Mar 19 '17 at 05:07
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    You can try and see. It is not that you will be able to damage the X-ray as metal is common in teeth. (I am not sure if the smoke will come out of the electronics? :-) – skvery Mar 19 '17 at 05:47
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    While it's not strictly design, a good answer could be useful to hobbyists or small enterprises considering BGA packages, but put off by inspection difficulties. –  Mar 19 '17 at 13:52
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    Maybe this will be of help: Fran Blanche did a video about xraying PCB - https://www.youtube.com/watch?v=zWGpF05zhdU, and Mike Harrison did a few too: https://www.youtube.com/user/mikeselectricstuff/search?query=xray – desqa Mar 19 '17 at 21:09
  • Be very aware of using this type of equipment if you are not trained to do so. [There were accidents](https://en.wikipedia.org/wiki/Goi%C3%A2nia_accident) from people who didn't know what they were doing in the past. (This makes me chill every time I read the events chain in this fact) – ricardomenzer Mar 21 '17 at 11:58
  • @ricardomenzer I have no plans to operate the machine myself, I will leave that to professionals. – BarrowWight Mar 22 '17 at 22:59
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    @ricardomenzer that was a radiotherapy source, not an x-ray machine. Much higher radiation levels and derived from a nuclear source (so it' can't be turned off, only blocked). – Peter Green Nov 17 '19 at 14:56

2 Answers2

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Ff you use a dental X-ray machine to look at PCB, it will not provide you with all the details you need in a PCB.

See for yourself in this picture made using a dental X-ray machine to look at a PCB:

enter image description here

JRE
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Basheer Khlaif
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    What do you mean? This is wonderful, and with a bit of a machine vision processing, it will distill the traces for each layer out of the picture. You should have no problem following the traces manually either. The only problematic spots are high absorption areas like ceramics, chip leadframes, and crystal covers and shields. You of course need several pictures taken, and then reassemble them, but you've basically disproven your assertion right here. And people upvote this? Wat? – Kuba hasn't forgotten Monica Jul 01 '21 at 19:20
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    I love how the text and the photo completely disagree. That resolution is well over 2x the minimum required for inspection. – Navin Apr 09 '22 at 11:08
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Yes, it can be used for that purpose, and it works well. You need to remember that the pictures are small, so several will need to be taken, with some overlap. Ideally you'd want the X-rays taken with a digital sensor, so there'll be no wait to develop the prints, and it should cost much less.

Kuba hasn't forgotten Monica
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