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I can sympathize with that, to some extent. Theory is an integral part of The Scientific Method (TSM), which has been a popular way to try to understand physical reality for several years now. There are other approaches to understanding physical reality, some more successful than others, depending on your criteria for success. My next most favorite approaches are "women's intuition" followed by "divine revelation" and wild ass guessing (WAG).
With TSM, you begin with one or more observations of some aspect of physical reality. Like, when I connect wires randomly to a large battery and a transistor, sometimes the transistor and the wires get very hot and smoke appears. This is my observation. Hooking up the wires is my experiment. Now, to explain what happened, I propose a theory. To test my theory I perform another experiment and observe the result. If the results agree with the expectations of my theory, I gain confidence that my theory probably describes reality... at least to the extent that my theory leads to repeatable and predictable results. That pretty much is all TSM is about: experiment, observe, explain, predict, experiment again to verify predictions..
TSM always generates lots of theories. Unfortunately, theories can NEVER be proven to be true! Why is that? Because all it takes is ONE counter-example to prove a theory is wrong. Some theories hang around for a long time because no one has found a counter-example that refutes them. Such theories can then take on the status of Laws. Ohm's Law, Newton's Laws are just two examples. Sometimes a counter-example refutes only part of a theory, so we don't have to completely discard the theory, just modify it a little to account for the counter-example. Newtons's Laws as "modified" by Einstein's theory of relativity is an example.
So, as your knowledge of electronics grows, so too should your knowledge of theory. Sometimes it's hard to figure out which theories you need to know to accomplish something productive. So start with simple theories that explain simple things. When you find counter-examples that a theory does not explain, and you need to understand why those counter-examples exist, go look for another theory that does explain the counter-examples. Or not. Sometimes useful things can be accomplished without understanding everything going on.
Look at how many Space Shuttles were launched without incident, and apparently without anyone understanding how "O"-rings might get hard and lose their ability to seal if subjected to overnight cold temperatures... in Florida of all places! The theory was available, but no one realized how important it was on launch day... well almost no one. I read or heard later that there were some dissenting voices that didn't want to launch, but these were dismissed. Bye bye, Columbia.
Yes, actually using stuff is a great way to learn. Use this with some elementary text books that explain why and how. We progress by learning from others because it saves a lot of time that might otherwise be wasted "re-inventing the wheel." Keep a laboratory notebook to record your progress and your ideas, even those ideas that don't work as expected. Well, especially those ideas that don't work as expected at first. We all learn from our mistakes, and the smarter ones among us learn from the mistakes of others.
The emitter is NOT always connected to ground. It depends on the circuit. The arrow points in the direction of conventional current flow, from positive to negative. So get over it. I did.
The primary function of a transistor is to control the flow of electrical current. There are many ways to do this, one being to use the transistor as a switch.
There are no stupid questions, but there is a plethora of stupid answers, especially on the Internet. Always experiment to separate the chaff from the few grains of "wheat" you might find here. Check references to help determine credibility. Google and other search engines will help you find out about things, but always compare the search results and sources for consistency and accuracy.
I can sympathize with that, to some extent. Theory is an integral part of The Scientific Method (TSM), which has been a popular way to try to understand physical reality for several years now. There are other approaches to understanding physical reality, some more successful than others, depending on your criteria for success. My next most favorite approaches are "women's intuition" followed by "divine revelation" and wild ass guessing (WAG).
With TSM, you begin with one or more observations of some aspect of physical reality. Like, when I connect wires randomly to a large battery and a transistor, sometimes the transistor and the wires get very hot and smoke appears. This is my observation. Hooking up the wires is my experiment. Now, to explain what happened, I propose a theory. To test my theory I perform another experiment and observe the result. If the results agree with the expectations of my theory, I gain confidence that my theory probably describes reality... at least to the extent that my theory leads to repeatable and predictable results. That pretty much is all TSM is about: experiment, observe, explain, predict, experiment again to verify predictions..
TSM always generates lots of theories. Unfortunately, theories can NEVER be proven to be true! Why is that? Because all it takes is ONE counter-example to prove a theory is wrong. Some theories hang around for a long time because no one has found a counter-example that refutes them. Such theories can then take on the status of Laws. Ohm's Law, Newton's Laws are just two examples. Sometimes a counter-example refutes only part of a theory, so we don't have to completely discard the theory, just modify it a little to account for the counter-example. Newtons's Laws as "modified" by Einstein's theory of relativity is an example.
So, as your knowledge of electronics grows, so too should your knowledge of theory. Sometimes it's hard to figure out which theories you need to know to accomplish something productive. So start with simple theories that explain simple things. When you find counter-examples that a theory does not explain, and you need to understand why those counter-examples exist, go look for another theory that does explain the counter-examples. Or not. Sometimes useful things can be accomplished without understanding everything going on.
Look at how many Space Shuttles were launched without incident, and apparently without anyone understanding how "O"-rings might get hard and lose their ability to seal if subjected to overnight cold temperatures... in Florida of all places! The theory was available, but no one realized how important it was on launch day... well almost no one. I read or heard later that there were some dissenting voices that didn't want to launch, but these were dismissed. Bye bye, Columbia.
Yes, actually using stuff is a great way to learn. Use this with some elementary text books that explain why and how. We progress by learning from others because it saves a lot of time that might otherwise be wasted "re-inventing the wheel." Keep a laboratory notebook to record your progress and your ideas, even those ideas that don't work as expected. Well, especially those ideas that don't work as expected at first. We all learn from our mistakes, and the smarter ones among us learn from the mistakes of others.
The emitter is NOT always connected to ground. It depends on the circuit. The arrow points in the direction of conventional current flow, from positive to negative. So get over it. I did.
The primary function of a transistor is to control the flow of electrical current. There are many ways to do this, one being to use the transistor as a switch.
There are no stupid questions, but there is a plethora of stupid answers, especially on the Internet. Always experiment to separate the chaff from the few grains of "wheat" you might find here. Check references to help determine credibility. Google and other search engines will help you find out about things, but always compare the search results and sources for consistency and accuracy.
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