I guess I didn't know this because I skip any chapter or paragraph named the dreaded "theory".In that case you will remain blind, and will remain as successful as a 3yo child randomly performing actions to see what happens.Not quite true. I mostly work with digital and hardware stuff which, as I see it, I have done quite well. Until the time comes when I am designing a complex product or anything else that requires full knowledge of what's going on, I wont bother wasting my time reading theory's. For now I'm happy enough knowing how to put something to gather without know why it works.
... if it works, and under what circumstances it won't work.It mostly does work (much to the disappointment of Dave ) and if it don't work I usually manage to fix it. If not I know where to come .Quotedo you think it is important to understand the theory of metastability, bridging terms and correct line termination, for example?Only if I need to. I learn as I go or require.
Kind of off topic but if you had 80 AA batteries (120 volts without an awesome batterizer bateroo) in series, you could connect the + side of the battery bank to a meters red (positive lead for example),and connect the black lead to a grounding rod and see +120 volts? Or what if you connected up the the negative of the batt to the red lead you would see -120 volts? I thought that AC power could do that because ultimately the negative of the generator at the power station was tied into the plug(forget that it three phase keep it simple at = and +)? Now after reading this thread I don't understand the negative voltage.
..... because ultimately the negative of the generator at the power station was tied into the plug
... if you had 80 AA batteries (120 volts without an awesome batterizer bateroo) in series, you could connect the + side of the battery bank to a meters red (positive lead for example),and connect the black lead to a grounding rod and see +120 volts? Or what if you connected up the the negative of the batt to the red lead you would see -120 volts? I thought that AC power could do that because ultimately the negative of the generator at the power station was tied into the plug(forget that it three phase keep it simple at = and +)? Now after reading this thread I don't understand the negative voltage.
So why can you measure between hot and ground?
And if you don't know the theory you cannot know that you "need to"! If forgotten, get the things that I mentioned wrong and the equipment will usually work on the bench, but will cause intermittent failures in the field.
Software equivalents include two-phase transactions, priority inversion (infamously on Mars), cache coherence...
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And if you don't know the theory you cannot know that you "need to"! If forgotten, get the things that I mentioned wrong and the equipment will usually work on the bench, but will cause intermittent failures in the field.
Software equivalents include two-phase transactions, priority inversion (infamously on Mars), cache coherence...As I said I learn as I go or require. For the small amount of work I'm doing, I don't want/have the time to study theory. If I do, and end up up not doing electronics for a few months I will forget it.
The last time I had a reread of my first electronics book "electronics for dummies " (which despite the name is not a bad book) was when I was 14.
If I need any quick theory such as an LC circuit I just read the section I need In "practical electronics for inventors" (one of the best electronics books in my opinion )
Obviously, this has its consensuses which is my this topic is here.
The only failure in the field was a public display with a row of buttons to choose what topic you want. The microcontroller sends serial strings to a c# program with a web bowser built in and when the program receives a number from the serial port it sends a keystroke (alt+x) x been the number received to select a html accesskey. This is only a software bug and can be fixed easily.
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And if you don't know the theory you cannot know that you "need to"! If forgotten, get the things that I mentioned wrong and the equipment will usually work on the bench, but will cause intermittent failures in the field.
Software equivalents include two-phase transactions, priority inversion (infamously on Mars), cache coherence...As I said I learn as I go or require. For the small amount of work I'm doing, I don't want/have the time to study theory. If I do, and end up up not doing electronics for a few months I will forget it.
The last time I had a reread of my first electronics book "electronics for dummies " (which despite the name is not a bad book) was when I was 14.
If I need any quick theory such as an LC circuit I just read the section I need In "practical electronics for inventors" (one of the best electronics books in my opinion )
Obviously, this has its consensuses which is my this topic is here.
The only failure in the field was a public display with a row of buttons to choose what topic you want. The microcontroller sends serial strings to a c# program with a web bowser built in and when the program receives a number from the serial port it sends a keystroke (alt+x) x been the number received to select a html accesskey. This is only a software bug and can be fixed easily.
The last statement deserves another "Oh. Good. Grief". I hope you have a good lawyer.
this. The bit before the "contents" panel is sufficient.
I do not fancy I know what I do not know
Kind of off topic but if you had 80 AA batteries (120 volts without an awesome batterizer bateroo) in series, you could connect the + side of the battery bank to a meters red (positive lead for example),and connect the black lead to a grounding rod and see +120 volts? Or what if you connected up the the negative of the batt to the red lead you would see -120 volts? I thought that AC power could do that because ultimately the negative of the generator at the power station was tied into the plug(forget that it three phase keep it simple at = and +)? Now after reading this thread I don't understand the negative voltage.
But what about an isolated ground, like the one I use for my SDR. It works as a circuit for the antenna.
But what about an isolated ground, like the one I use for my SDR. It works as a circuit for the antenna.
I'm afraid I find that question a bit confusing. Isolated ground as a circuit for the antenna? what?
So why can you measure between hot and ground?
This may sound a bit anal .... but I ask for good reason:
1. What do you define as "hot"
and
2. What do you define as "ground"
So why can you measure between hot and ground?
This may sound a bit anal .... but I ask for good reason:
1. What do you define as "hot"
and
2. What do you define as "ground"
So to keep it simple forget my SDR comment.
Hot is the right side contact on a US 110VAC plug, its the one that has the voltage.
Neutral is the opposite contact that is connected to your house's ground and the other side of the power line to your house.
Ground is the round contact that connects to your houses grounding rod. Thats how I think of it. So how did early telegraph lines work that only used one wire? I always thought of a circuit as a loop. When you plug something in at your house you are ultimately connecting to both terminals on the power stations generator. So why can current flow when you only connect to one (hot side AC connector) and your houses ground? Thats not making a loop.
So how did early telegraph lines work that only used one wire? I always thought of a circuit as a loop.
When you plug something in at your house you are ultimately connecting to both terminals on the power stations generator. So why can current flow when you only connect to one (hot side AC connector) and your houses ground? Thats not making a loop.
So how did early telegraph lines work that only used one wire? I always thought of a circuit as a loop.A circuit is a loop. It is always a loop. If there is current flowing, there will be a loop. Sometimes it may not be obvious, but it HAS to be there.
The old telegraph worked by having one wire up in the air - isolated from the soil. The soil becomes the other conductor...QuoteWhen you plug something in at your house you are ultimately connecting to both terminals on the power stations generator. So why can current flow when you only connect to one (hot side AC connector) and your houses ground? Thats not making a loop.The loop is there....
Your second image isn't quite right though, because as I said in my last post, neutral and ground are bonded at the panel. If you had to rely on the actual ground as a return, there would be a significant voltage drop, because that ground could be quite a high impedance depending on several factors (distance from substation or transformer, ground rod depths, soil moisture, soil type and so on).
Your second image isn't quite right though, because as I said in my last post, neutral and ground are bonded at the panel. If you had to rely on the actual ground as a return, there would be a significant voltage drop, because that ground could be quite a high impedance depending on several factors (distance from substation or transformer, ground rod depths, soil moisture, soil type and so on).
Better?
So how did early telegraph lines work that only used one wire? I always thought of a circuit as a loop.A circuit is a loop. It is always a loop. If there is current flowing, there will be a loop. Sometimes it may not be obvious, but it HAS to be there.
-Snip-QuoteWhen you plug something in at your house you are ultimately connecting to both terminals on the power stations generator. So why can current flow when you only connect to one (hot side AC connector) and your houses ground? Thats not making a loop.The loop is there....
Your second image isn't quite right though, because as I said in my last post, neutral and ground are bonded at the panel. If you had to rely on the actual ground as a return, there would be a significant voltage drop, because that ground could be quite a high impedance depending on several factors (distance from substation or transformer, ground rod depths, soil moisture, soil type and so on).
Your house ground and neutral are bonded at the circuit breaker box. The ground is also connected to a grounding round driven a certain distance into the soil.
The reason ground is literally grounded is for fault protection (think about the neutral wire breaking on the power pole or in your breaker box).
A word of warning (which I suspect Tim already knows), that scheme (ground and neutral bonded at the building's incomer) is not universal.