Does anybody know what that "f" looking sign is next to the 5, left-hand bottom corner of the LED labeling?:
It Indicates the diameter of the LED package.
Summary of Conclusion: Don't seek precision unless you have the means to obtain it.
...I'm a young electronics hobbyist, who has the passion to become a robotics engineer at later stages of my maturity.
Lately I have been tinkering with my first circuit designs, simple stuff really. My first circuits were "plug-and-play", based off of rough, highly in-precise calculations, but it would get things lit like the image below:
Later, I decided to revise my scketch, adding in LED's and using a more scientific method to make more precise calculations about the circuits functionality...
Long story, but I got my circuit working. Thanks.