Anyone interested in Electronics?
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I am :)
I took it as a GCSE (in England when you are in year (Americans: read "grade") 10 and 11, you take a series of tests (or modules) called "GCSEs" which stands for General Certificate of Secondary Education. I don't really know how to explain it, but we have GCSEs (used to be called O levels, I think the O was for ordinary) and then A Levels (which consists of "AS" and "A2" and is voluntary). Then you can voluntarily go on to University or whatever.
Anyway, so I recently started enjoying it more and more. Making circuits I enjoy, and am relatively good at (I understand what I make at least).
What about you?
Below is an early stage development of a circuit I have to make:
http://i34.tinypic.com/28tf2w0.png
It's supposed to be an alarm, but it's quite simple. As the software we use can't emulate micro controllers I can't use them and thus it would be difficult to add anything like a passcode to reset the circuit.
+25 points to anyone that figures out what it does, in what order and what each stage does individually (e.g. the two switches -> the two NANDS -> the two NPNs -> the NE555 timer -> outputs).
By the way, I hate breadboarding with a passion.
I took it as a GCSE (in England when you are in year (Americans: read "grade") 10 and 11, you take a series of tests (or modules) called "GCSEs" which stands for General Certificate of Secondary Education. I don't really know how to explain it, but we have GCSEs (used to be called O levels, I think the O was for ordinary) and then A Levels (which consists of "AS" and "A2" and is voluntary). Then you can voluntarily go on to University or whatever.
Anyway, so I recently started enjoying it more and more. Making circuits I enjoy, and am relatively good at (I understand what I make at least).
What about you?
Below is an early stage development of a circuit I have to make:
http://i34.tinypic.com/28tf2w0.png
It's supposed to be an alarm, but it's quite simple. As the software we use can't emulate micro controllers I can't use them and thus it would be difficult to add anything like a passcode to reset the circuit.
+25 points to anyone that figures out what it does, in what order and what each stage does individually (e.g. the two switches -> the two NANDS -> the two NPNs -> the NE555 timer -> outputs).
By the way, I hate breadboarding with a passion.
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The two nand gates form a latch. Only one will be on at a time - and as one of the outputs is connected to the Darlington transistor pair driver, then the Darlintion is on or off depending
on the nand gate status.
The output of the nand gates also drives the output LED (D4) via IC4 and transistor Q7.
One of the switches seem to be an on switch (SW2), the other an off switch (sw3). (could be the otherway around?)
The 555 timer is in astable mode and once the Darlingtion is on, the timer will will set out a stream of pulses which will drive the buzzer (via Q6). The buzzer LED (D1) will also flash.
(It has been 25 years since I did my electronics course - so I maybe a bit rusty)
Edit:
the timer is in astable mode not a stable mode
on the nand gate status.
The output of the nand gates also drives the output LED (D4) via IC4 and transistor Q7.
One of the switches seem to be an on switch (SW2), the other an off switch (sw3). (could be the otherway around?)
The 555 timer is in astable mode and once the Darlingtion is on, the timer will will set out a stream of pulses which will drive the buzzer (via Q6). The buzzer LED (D1) will also flash.
(It has been 25 years since I did my electronics course - so I maybe a bit rusty)
Edit:
the timer is in astable mode not a stable mode
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As I say I maybe a bit rusty - but what keeps the nand gates from powering up in the ON state - so that on power up the buzzer and light don't start operaing
You know, if there's one thing I simply can't wrap my head around, is electronics. The only things I've been able to understand are the most trivial of circuits, and logical gates, and the latter only in their abstracted forms. I've read it many times, but I've never understood how transistors work, and I don't mean how they work internally, I mean what they do under what conditions.
Oh, well. At least I can understand why I should never open up a TV.
The NANDs form an SR flip-flop (http://en.wikipedia.org/wiki/Flip-flop_%28electronics%29#Set.E2.80.93reset_flip-flops_.28SR_flip-flops.29 ), if I'm not mistaken. Depending on the input, the flip-flip can output 0, 1, hold the previous output, or produce a race condition.
I think the truth table for this case is:
1 6 3
0 0 Hold
0 1 0
1 0 1
1 1 Unstable
The two switches obviously act as the input of the flip-flop.
This doesn't seem very smart. Wouldn't it be easier to just buy a flip-flop rather than buy gates and build one out of them? And why an SR? Is the race condition desirable?
Oh, well. At least I can understand why I should never open up a TV.
The NANDs form an SR flip-flop (http://en.wikipedia.org/wiki/Flip-flop_%28electronics%29#Set.E2.80.93reset_flip-flops_.28SR_flip-flops.29 ), if I'm not mistaken. Depending on the input, the flip-flip can output 0, 1, hold the previous output, or produce a race condition.
I think the truth table for this case is:
1 6 3
0 0 Hold
0 1 0
1 0 1
1 1 Unstable
The two switches obviously act as the input of the flip-flop.
This doesn't seem very smart. Wouldn't it be easier to just buy a flip-flop rather than buy gates and build one out of them? And why an SR? Is the race condition desirable?
@guestgulkan;
Very nearly!
SW2 is a latching on switch and SW3 is a reset, or off switch.
You didn't mention that D4 (I think the software numbers them and doesn't renumber them when you delete one, at one time I had 8 LEDs and 4 buzzers. Unfortunately I couldn't make the wires thicker so the electricity could get through better) is constantly on if the reset is off due to the inverter.
@Helios;
it would, but as it's school and they do everything as cheaply as possible, this is probably the only way to do it. Or it may be that I'll get more marks this way.
One of the people in my class added 6 random NANDS connected directly to the 0 V for more marks.
The mark scheme, obviously, is pathetic.
Very nearly!
SW2 is a latching on switch and SW3 is a reset, or off switch.
You didn't mention that D4 (I think the software numbers them and doesn't renumber them when you delete one, at one time I had 8 LEDs and 4 buzzers. Unfortunately I couldn't make the wires thicker so the electricity could get through better) is constantly on if the reset is off due to the inverter.
@Helios;
it would, but as it's school and they do everything as cheaply as possible, this is probably the only way to do it. Or it may be that I'll get more marks this way.
One of the people in my class added 6 random NANDS connected directly to the 0 V for more marks.
The mark scheme, obviously, is pathetic.
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What is it about electronics that you don't understand?
Chemistry is something I can't get. No matter what, I just don't see how it works. And then, what if, in 1000 years, people say "Wow; those 20th/21st Century Scientist were dumb. They thought that everything was made out of flying orbs with more flying orbs flying around them... idiots." and we say religion doesn't make sense...
At least friction --> heat makes sense. You can prove it by rubbing your hands together, they quickly warm up.
Another thing that doesn't make sense is "energy can't be created or destroyed, only converted". Where did it all come from then? I think my physics teacher said something about Hydrogen colliding making Helium atoms --> every other atom. If he's right then there are no elements except hydrogen, everything else is just more hydrogen.
Thinking about it, the big bang makes no sense. If matter can't be created, then how did it all get here? The big bang is supposed to be the expansion of a small (but maybe dense) amount of matter into the universe (which is proven by Red Shift), right? Then where did that matter come from? People will say "God" or even "Gods". But that doesn't make sense either: basically, by saying God made everything you're saying "Nothing came from nowhere and created everything."
Ow, my perspective hurts...
Chemistry is something I can't get. No matter what, I just don't see how it works. And then, what if, in 1000 years, people say "Wow; those 20th/21st Century Scientist were dumb. They thought that everything was made out of flying orbs with more flying orbs flying around them... idiots." and we say religion doesn't make sense...
At least friction --> heat makes sense. You can prove it by rubbing your hands together, they quickly warm up.
Another thing that doesn't make sense is "energy can't be created or destroyed, only converted". Where did it all come from then? I think my physics teacher said something about Hydrogen colliding making Helium atoms --> every other atom. If he's right then there are no elements except hydrogen, everything else is just more hydrogen.
Thinking about it, the big bang makes no sense. If matter can't be created, then how did it all get here? The big bang is supposed to be the expansion of a small (but maybe dense) amount of matter into the universe (which is proven by Red Shift), right? Then where did that matter come from? People will say "God" or even "Gods". But that doesn't make sense either: basically, by saying God made everything you're saying "Nothing came from nowhere and created everything."
Ow, my perspective hurts...
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| What is it about electronics that you don't understand? |
Maybe if I really wanted, I could understand it, but I don't really care. I already have my thing.
Besides, programming has one thing electronics doesn't:
| The programmer, like the poet, works only slightly removed from pure thought-stuff. He builds castles in the air, from air, creating by exertion of the imagination. Few media of creation are so flexible, so easy to polish and rework, so readily capable of realizing grand conceptual structures. |
I'll tell you what really doesn't make sense: contact. Think about it. Atoms are really, really, really empty spaces. You can't have two atoms touching. And yet, macroscopic objects still don't go through each other. What the hell?
| I think my physics teacher said something about Hydrogen colliding making Helium atoms --> every other atom. If he's right then there are no elements except hydrogen, everything else is just more hydrogen. |
| Thinking about it, the big bang makes no sense. |
As I understand it, the theory explains the origin of the universe as the violent decompression of space. It doesn't attempt to explain why space was compressed, how long it was in this state (that question, by the way, doesn't make sense. Time is thought to start at the BB), or where the matter that was compressing it came from. I don't think it even explains why it happened, since that would also involve something happening before the event, which is absurd.
| "Nothing came from nowhere and created everything." |
Here's another: The universe is a simulation running on a hypercomputer. At one point, some race born in this universe will build an equivalent hypercomputer and run a universal simulation identical to this one. The simulation will of course finish in finite time. This universe will exist forever.
That's not more nor less rational, but it does take longer to type.
And it's also mind-blowingly awesome when you think about it.
| It's not just one thing. I lack the reasoning skills to follow circuits. It's probably similar to how normal people see code. Maybe if I really wanted, I could understand it, but I don't really care. I already have my thing. |
Normal people? lol, unfortuantely, i agree. Despite the BSEE I received this past May, I still don't understand, which generally just means I don't want to. Amazing that one can graduate Summa Cum Laude and not understand a thing about the subject.
| If he's right then there are no elements except hydrogen, everything else is just more hydrogen. |
No, but you're arguing English and definition, not science or philosophy. Hydrogen is described as the composition of a certain number or elements in a certain arrangement, and it so happens that when these combinations smash together sometimes they produce larger more complex arrangements of elements that we give other names to like Helium, etc.
| I'll tell you what really doesn't make sense: contact. Think about it. Atoms are really, really, really empty spaces. You can't have two atoms touching. And yet, macroscopic objects still don't go through each other. What the hell? |
No way! This is one of the things I love most about perspective. It may not be intuitive, but it doesn't not make any sense. We assumed that we were always "touching" things because we perceive it that way, and as such we may define "touching." But as you've pointed out, we're never actual in matter-contact, we're in energy-contact. I think no two things have ever been in matter-contact - I don't think that is possible - which is just more evidence for the theories that everything is made out of some less-matter-like and more-energy-like stuff.
| big bang |
Too much to type here, but helios explained well. I love when people ask "what came BEFORE the big bang" ...nothing can come BEFORE because BEFORE is a concept of time which didn't exist BEFORE the big bang... ow.
| Then where did that matter come from? People will say "God" or even "Gods". But that doesn't make sense either |
I never understood why people ever thought "God" was a good answer to "it couldn't have come from nowhere, so where did it come from." My follow-up is always "okay, wonderful, now where did God come from?" and those people are usually more content to believe that "God" always existed, but not "matter" or more importantly "the universe and whatever it may be composed of at whatever time (if time exists at that time, ow)."
I think one of the biggest problems some people have with the BBT is their perception of time. Time is not a constant. It is, in fact, very closely tied to space. Time-Space is not just a cool Fictional term you here in movies.
It's fairly commonly known that as you approach the speed of light, time slows down, effectively stopping at the speed of light. So you could say that time does not exist for light.
Time also slows down as gravity increases, which is related to how gravity distorts space. Before the Big Bang, all existence was compressed into a dimensionless point. There was no space, so there was no time.
It's fairly commonly known that as you approach the speed of light, time slows down, effectively stopping at the speed of light. So you could say that time does not exist for light.
Time also slows down as gravity increases, which is related to how gravity distorts space. Before the Big Bang, all existence was compressed into a dimensionless point. There was no space, so there was no time.
Here's something nice and paradoxical; is teleportation of humans possible?
I think no; the way teleportation would work would be something like process forking, except the parent process is killed. You would copy the exact genetical information of the person and send it somewhere and then "rebuid them". But do you rebuild them before destroying them, or before? If you rebuild them before; then there are two of the same person in existance, even if only for a split second. But if you rebuild them after; then they would have died and been resurrected! I think it's possible to teleport objects though as they do not need to be kept alive. Think how cool it would be if you could order something, e.g. a pizza, and then the pizza company sends your computer data which says:
* The structure of the pizza
* The ingredients of the pizza
* Instructions on how to build the pizza
you are then sent the ingredients as electrical pulses (your computer would have to be able to create the ingredients itself based on the instructions it recieves).
Then you could use a memory debugger to find out all ten spices in KFC chicken :)
I also just realised something about where I live.
http://maps.google.co.uk/maps?hl=en&source=hp&q=hextable&gbv=2&ie=UTF-8&sa=N&tab=il&start=0
I live six miles from somewhere called "Hex table". Win!
I think no; the way teleportation would work would be something like process forking, except the parent process is killed. You would copy the exact genetical information of the person and send it somewhere and then "rebuid them". But do you rebuild them before destroying them, or before? If you rebuild them before; then there are two of the same person in existance, even if only for a split second. But if you rebuild them after; then they would have died and been resurrected! I think it's possible to teleport objects though as they do not need to be kept alive. Think how cool it would be if you could order something, e.g. a pizza, and then the pizza company sends your computer data which says:
* The structure of the pizza
* The ingredients of the pizza
* Instructions on how to build the pizza
you are then sent the ingredients as electrical pulses (your computer would have to be able to create the ingredients itself based on the instructions it recieves).
Then you could use a memory debugger to find out all ten spices in KFC chicken :)
I also just realised something about where I live.
http://maps.google.co.uk/maps?hl=en&source=hp&q=hextable&gbv=2&ie=UTF-8&sa=N&tab=il&start=0
I live six miles from somewhere called "Hex table". Win!
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If you were to bend space, you wouldn't need to go through all that. It'd be just like walking across a room. Only the two sides of the room are actually an arbitrary distance from each other.
Even if that wasn't the case, you wouldn't copy the genetic information. You'd copy the material information.
There's no way to know what the person being copied and destroyed feels. From a purely materialistic point of view, the person that comes out the other side identical to the original for every possible measurement, including their own, but not the same, and destroying the one on this side is murder.
If people are actually dual (http://en.wikipedia.org/wiki/Dualism_%28philosophy_of_mind%29 ), then it becomes rather complicated.
How is this related to electronics, again?
Even if that wasn't the case, you wouldn't copy the genetic information. You'd copy the material information.
There's no way to know what the person being copied and destroyed feels. From a purely materialistic point of view, the person that comes out the other side identical to the original for every possible measurement, including their own, but not the same, and destroying the one on this side is murder.
If people are actually dual (http://en.wikipedia.org/wiki/Dualism_%28philosophy_of_mind%29 ), then it becomes rather complicated.
How is this related to electronics, again?
Bending space? You believe in string theory? I do.
It's not, the thread has been derailed. I just derailed it even more :)
It's not, the thread has been derailed. I just derailed it even more :)
| You believe in string theory? |
The question itself is absurd. Since when do scientific theories need to be believed in?
Bending space has nothing to do with string theory (at least not as far as I can tell). It happens routinely around gravity wells. It's just a matter of bending it far enough to make it loop on itself.
To give an approximate example of what this would look like from our perspective, the portals in Portal work exactly like this.
I'm not sure if it's possible to have 2D portals in 3D space. It would raise the question of what's behind the portal, and whether the portal's edges are hazardous. I think they would have to be 3D spaces. If that's the case, the inside of the portal on one side would be the outside on the other. The universe would be inside itself! Twice!
Yeah, 2D portals in 3D would be weird. 3D portals reminds me of the 3D mobious jar thing.
| Since when do scientific theories need to be believed in? |
Perhaps I should have said "agree with"...
| Bending space has nothing to do with string theory |
No, it's the theory that everything is made of string or something.
| String theory is a developing branch of theoretical physics that combines quantum mechanics and general relativity into a quantum theory of gravity.[1] The strings of string theory are one-dimensional oscillating lines, but they are no longer considered fundamental to the theory, which can be formulated in terms of points or surfaces too. |
closed account (z05DSL3A)
| You believe in string theory? |
| The question itself is absurd. Since when do scientific theories need to be believed in? |
| Perhaps I should have said "agree with"... |
Believe is the correct word, your original question might have been phrased better such as 'Do you believe string theory?' but still the question you asked is not absurd. In saying something like 'I believe in string theory', you are saying that you are confident that string theory is correct.
Well the verb to 'believe' usually has connotations with things like religion... I do think string theory makes sense though and I am somewhat confident it is correct.
"Belief" implies "faith", which is the acceptance of a claim as fact without the need of proof.
Then I definately didn't mean belief. I don't accept it as fact, I think it probably is, but I will require proof before I make up my mind.
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