# DIY inspection microscope for SMD work

#### THE_RB

Joined Feb 11, 2008
5,438
Hi, maybe this is of interest.

I wanted a standalone flatscreen microscope for SMD work, and made one out of an old VGA PC monitor and a couple of cheap ebay items.

http://www.romanblack.com/VGA_microscope/VGAmic.htm

I know you can buy cheap USB "microscopes" that plug into a PC, but I made this one more for workshop use and personally I hate having to tie up a PC by having a tool plugged into it.

#### kubeek

Joined Sep 20, 2005
5,758
I use a 10x jewler's loupe with triplet optics and I never had to use a microscope. If you are able to solder under this than it could be a help, but a microscope is much less flexible for detail inspections than a loupe, especially when you need to view a chip from the side.

#### spinnaker

Joined Oct 29, 2009
7,835
I use a 10x jewler's loupe with triplet optics and I never had to use a microscope. If you are able to solder under this than it could be a help, but a microscope is much less flexible for detail inspections than a loupe, especially when you need to view a chip from the side.
Spoil sport.

#### ErnieM

Joined Apr 24, 2011
8,181
Congrats RB, that's a pretty cool idea. I especially like the "zero engineering" design done with all off-the-EBay parts. We string chips together to do things, why not complete modules?

I imagine it must be much easier to view then a "real" (conventional? optical?) microscope: mine gives me a bit of eyestrain after a long day. It feels like my eye balls are being sucked out.

CRT monitors are free for the asking, and the initial crop of 14-15" monitors are also seeing the curbside for trash pickup too. Heck, I can drive to Microcenter and get a refurb 15" for 50 bucks (USD), but only if I forget I have one stashed in my shed in case my 22" ever fails.

You should perhaps submit this to the completed projects section.

I use a 10x jewler's loupe with triplet optics and I never had to use a microscope. If you are able to solder under this than it could be a help, but a microscope is much less flexible for detail inspections than a loupe, especially when you need to view a chip from the side.
I use my microscope all the time to view chips from their sides. You just tilt the board over.

Besides, I kinda like a big piece of metal between my face and nose and a hot tip of molten metal giving off who knows what fumes?

I'd burn my nose off if I just used my loupe to solder (and I have a loupe too).

#### kubeek

Joined Sep 20, 2005
5,758
I didn't actually mean soldering under a loupe, just that for inspecting the board afterwards it easier and faster to focus a loupe on a particular point and get just the right light than setting a board under a microscope.

#### THE_RB

Joined Feb 11, 2008
5,438
Hi Kubeek, I already have an assortment of head mounted and handheld magnifiers, illuminated large magnifiers and jeweller's loupes etc.

For sure it's really handy when inspecting chip leg soldering etc to be able to tilt the PCB to an extreme angle and between and under legs. I allowed plenty fo room under the camera and can easily tilt a small PCB to 45 degrees or so.

Also the "fish eye" effect does a similar thing, because the focal distance is 30mm but the screen shows 35mm width of PCB, so parts near the edge of the screen are being viewed from an angle too.

This won't be my only SMD tool, I already have tools and procedures used for many years. Basically this will be used for flat inspection, like making sure a bare PCB has no bad tracks, or checking SMD parts have been placed properly before going in the oven to be soldered. Or easy reading of a heap of resistor values etc, you get the idea.

ErnieM said:
Congrats RB, that's a pretty cool idea. I especially like the "zero engineering" design done with all off-the-EBay parts. We string chips together to do things, why not complete modules?

I imagine it must be much easier to view then a "real" (conventional? optical?) microscope: mine gives me a bit of eyestrain after a long day. It feels like my eye balls are being sucked out.
...
Thanks Ernie, yes it's easier for bulk inspection tasks for sure, no neck strain etc as I can sit comfortable in a chair looking forward and just look at the parts on screen to check numbers and placements etc. All my other magnifiers need some fixing of my head and the angle etc and the light source to get good inspection.

It's not perfect, the camera image quality is down compared to say a properly setup USB->PC setup as this one converts camera->composite->different resolution VGA so some clarity is lost in conversions.

But at this magnification I can inspect solder joints ok and read all parts values, and it fits 35mm of PCB on screen, which is a lot, so for one re-position of the PCB I can then relax and inspect a lot fo parts without having to hold or move anything. That is the big benefit i think.

#### thatoneguy

Joined Feb 19, 2009
6,359
What is the total cost you have into this? I'd be interested in making one myself! My eyesight isn't as keen as it used to be, actually it is, but the writing and components have shrunk faster.

If the camera could be backed up about 4" and still focus so that a fan could move air in from one side, it would work for soldering SMD as well!

#### nerdegutta

Joined Dec 15, 2009
2,682
Nice!

Do you have a recording function?

I have nearly similar config. A super cheap web cam mounted in an old drillpress, and some magnifying glass underneath.

This is me inspecting a PCB.

http://youtu.be/0OVRBBYPiVI

Well done, RB!

#### THE_RB

Joined Feb 11, 2008
5,438
What is the total cost you have into this? I'd be interested in making one myself! My eyesight isn't as keen as it used to be, actually it is, but the writing and components have shrunk faster.

If the camera could be backed up about 4" and still focus so that a fan could move air in from one side, it would work for soldering SMD as well!

#### BReeves

Joined Nov 24, 2012
410
Brilliant, will have to build one of these. I also have a Veho USB microscope but this is much better. I have everything but the Video to VGA converter. Best I could find on eBay was $18.88 with shipping from Hong Kong. No problem other than it will take two weeks to get here. #### thatoneguy Joined Feb 19, 2009 6,359 It cost be$16 for the VGA converter, $14 for the camera, and a few bucks extra for the little plastic boxes and a few white LEDs. Total under$40. The monitor was a spare one I already had.

It won't be used for soldering as the fumes can foul the lens etc (as you know) and because I already have magnifiers for soldering touch ups, and because I use an oven and paste for larger SMD soldering jobs.

Hi Nerdegutta, nice setup! I have no need for recording. I tried with some magnifier lenses under the camera but ended up just adjusting the lens to give the macro focus. The "fish eye" problem has actually turned out to be a benefit in the long run.
That is pretty awesome. The only thing left for you to do is get a higher end PIC interfaced with the signal to draw reticules and measuring lines to ensure it came out the way it was intended. If you can slap together a spec scope for under \$200 (w/o display), you could make a bit selling kits! Big bonus for a mouse cursor with line/box drawing for 0.01mm level measurements on screen.