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In the distant past it was pretty easy to see what you were doing in electronics with the unaided eye. Parts were large, my eyesight was better, and traces were fatter. But today everything has become miniaturized. A toolscope, or some form of magnification is essential. When using your toolscope, you can easily feel like Gulliver inspecting the army of Lilliput.
I clearly remember the awe I felt when I first saw someone solder a chip with 100 pins. This is not a task that you can do with the unaided eye, or too much caffeine. Since those early days I have learned to perform this task myself. I have, as I am sure you have as well, hand soldered 0402 components. If you haven’t, you need to challenge yourself more. I would try an 0201, but I keep losing them.
Figure 1 G600 Digital Microscope
It’s on the upper right
Eventually in your career, you will want to share something you see under magnification. There are several options for doing this. You can describe what you see and try to navigate the other person so they see it too. If you happen to have a video camera on your toolscope the task is easy. What you want to show them is on the screen, just point at it.
If the person you want to show something to is not in your lab, you need to take a picture. How many of you have held your cell phone up to a toolscope and snapped a picture to email to someone? The ability to share and document is essential. And today there is no reason not to have a personal toolscope with camera and video for every engineer.
The ability to share information is greatly improved when an engineer can easily take and share a picture with others. Documentation is greatly improved as well as communication with fabrication and assembly houses.
Figure 2 Cell phone on toolscope.
In figure 1, it is easy to see there have been some hacks. Pin 3 was not connected to the plane that surrounds the chip. And R2 and R3 needed to be connected together. We all use Fabrication and Assembly documents but how many of us are using Design documents?
When the job is fairly straight forward I don’t keep a design document, but when the design requires me to make assumptions or if the design is complicated and I might want to document why I chose a particular value or designed a circuit in a specific way, I keep a design document. I have also found that this a good place to put photos like the one in Figure 1. These kinds of edits are important to document, so that when you go to make a new revision, they are listed right there for the next engineer. Remember, that next engineer might be you in 6 months and I guarantee you will have forgotten stuff by then, so be diligent at documenting your edits.
Break Out Another Thousand (BOAT)
It was not too long ago that any toolscope, let alone one with camera or video, cost thousands of dollars. Today you can buy fairly good quality tools for $15 to $150,000 depending on what you needs. The cheap $15 tools hook into your USB and work well enough for simple things. You can get a scope in the $40-$60 range that has camera and video. For a few hundred dollars you can get a camera attachment for your standard toolscope that will project an image onto your computer screen, snap photos or take video.
When you get in the range of tens of thousands to hundreds of thousands of dollars there are systems that not only take pictures, but also identify what they are looking at. These systems are used by the board assembly houses to check the proper placement of components. They can decide if a resistor is crooked, if a part is rotated 90 or 180 degrees (they don’t work well when you put them on wrong). They can even tell if the component is the wrong color, or if the markings on the top of the chip don’t match. High end systems are able to take accurate measurements and need calibration. Low end systems are good for communication with other humans.
Soldering under the scope
If you are used to soldering what you are looking at, then the first time you solder while looking through a toolscope or while looking up at a screen while your hands are working in front of you will be quite a challenging. Take it from me, it only takes a little practice to get good. Keep at it and go slow, and before you know it you will be able to do it without much thought.
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