Why there are missing components on stock devices’ boards?
The reason for this post is a friend of mine. I won’t reveal his personality and I will call him Peter.
Let me tell you the long story short…
About a week ago Peter came at our office frustrated and he told me something like:
“Emil, dude, I know you don’t have much time, but yesterday I received one stopmbox (guitar effect) from eBay and I doesn’t sound as I expected. I opened it and I think I am defrauded!!! There are missing elements from the board!!! It’s awful!!! I want to pay you to set them up.”
I immediately guessed what the deal was and I explained him. In order to tell you I made few images of what Peter has seen. Namely, the elements really were not soldered on the board.
You probably never asked yourself this question
or you never paid attention, but in many cases, when you open a factory devices and look at the boards, you’ll see really missing components. There are white stamp, but they are not soldered. First I want to reassure you. You are not screwed up! The reason to do the boards in such way is that the manufacturers save money. This does not mean that they are lying.
Normally a device may have several models or variations with different features and functionality.
In our case the manufacturer Blackstar have a product line of 6 similar effect pedals.
If we look at them the only difference we see is the signatures and the paint color. If we take a look inside we will find that they use one and the same PCBs (Printed Circuit Boards), but the variants are done by placing or not placing some electronic components. How does it save money? It’s possible because only one variant of the PCB is produced instead of 6 different. This makes it possible to order big quantity in production and to get discount. As you cans see this is applicable for the enclosures, the potentiometer knobs, and other details as well. This approach is widely used in prototyping. If you want to test several concepts or variants, you can make the design in such way that you can switch between the variants toggling some components. And what was the mystery at the end? Peter just bought the wrong model of the effect.