The laser etching used on many SMD parts can be very hard to read. For those that refuse to give up their secrets even under varied lighting and magnification, I have a trick that usually works quite well. All you need is a regular fluorescent highlighter pen and a UV light.
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Run the highlighter over the part, as if highlighting something on a page. Then, wipe off the surface with a dry wiper or swab.
The ink retained in the etching will fluoresce more than what remains on the surface, revealing the part number in (relatively) easy to read illuminated lettering. If you desire it, some isopropanol can clean off the ink, but it's probably not required.
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This has helped me in the past, I hope it can help someone else.
Show off I think you got busy with the tipex for those ones!Hello,
Can you read those?
Bertus
It is the 555 and almost impossible to read even with my gooseneck LED magnifier. I've wiped them, wetted them, used the gooseneck plus another magnifying glass to increase the magnification, turned them all directions trying to get a good light angle on the markings and this beats them hands down for me using what I already have.Hello,
I also think it is the NE555.
Do you have a flatbed scanner?
I made a scan of two chip I had laying around:
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Can you read those?
Bertus
I used to do that with Liquid Paper, but it's messy. If you see my post above, you'll see the method I replaced it with. More effective, less messy.For laser-etched markings, try smearing toothpaste or similar white goo over the surface. It fills the etch valleys and makes the marking distinct.
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You can get a cheap UV flashlight, it is also useful for curing UV adhesives and resins. Only a few dollars for a totally functional one.I don't have the UV lamp (haven't used an EPROM eraser since forever), but am adding it to the Wishlist now.
Glad it proved effective. I struggle with markings sometimes.Yaakov said:
Run the highlighter over the part, as if highlighting something on a page. Then, wipe off the surface with a dry wiper or swab. The ink retained in the etching will fluoresce
I just tore down several breadboards that had impossible to read chips. Did this and it works much easier and quicker than my photo and zoom method. I ran a yellow highlighter over them and didn't wipe them before flourescing. Works perfectly. Kudos to Yaakov!
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