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Note increased input VDCs, subsequent currents (thru the zener) and output voltages, from left to right of the examples.
The point is that the zener diode holds a generally stable output over a range of input voltages. There's a very good explaination of zener diode theory (with example schematics) here:
(here we go. Ol' CBB gonna try to s'plain how da watch works...)
Neither. and yet, both (as undifferentiated ENERGY).
That's why it's called a waveform. Don't really want to go into the physics of energy (since the Physicists don't really have it all worked out yet) BUT, just think of light as a waveform, or heat, that thing you see on an oscilloscope. They're not really something with substance.
The current is a wire is, literally, the electrons orbiting around the nucleus (as I said) being pushed/pulled along the wire by the difference in electrical potential (volts) from one end of the wire to the other ( + & - ). If they're all going one direction, then it is Direct Current (DC).
Electrons have mass, a physical presence, if you will. If you had a scale that could weigh something small, they would register weight: A powerful enough microscope, you could see them.
Now, if you take a voltage and rapidly vary it from 0 to +12 to 0 to -12 to 0 to +12, etc., you create Alternating Current (AC) that, on an oscilloscope, looks like a wave, i.e., if you took a rope, tied one end to a tree, and at the other end, after pulling it away from the tree, start rapidly shaking it up and down, up and down, you get the wave effect. Like a flag waving in the wind. All the electrons move one way down the wire, and then instantly change direction, back and forth, back and forth. (How many time a second they do that is call frequency of the wave).
A wave is more of a concept or, if you like, a description of how alternating voltages and current, as power, or energy are depicted. But they have no substance, and you cannot see them, only their affect on objects that behave a certain way if in the presence of waves.
That's not to say that there's no energy involved, it's just not the kind of energy we think of as electricity.
Fortunately, some very wise folks came up the math that let's us at least be able to control the stuff. How it all works, I'm quite sure, is just plain old magic.
so if this will clip power (you do realise that makes my waveform theory right **broken link removed** )
why do you need any more componants, is that what your saying **broken link removed** so the catch is they get very hot if you regulate current with them
ok, next question is if they can take the volts, how much current can they take, they are stating mA on datasheet, how about A's
edit: you posted again, so this post is about zener
(here we go. Ol' CBB gonna try to s'plain how da watch works...)
Neither. and yet, both.
only their affect on objects that behave a certain way if in the presence of waves.
That's not to say that there's no energy involved, it's just not the kind of energy we think of as electricity.
Fortunately, some very wise folks came up the math that let's usl at least be able to control the stuff. How it all works, I'm quite sure, is just plain old magic.
good, I like magic, so my theory of waveforms is sort of right, we use waveforms to measure so we can alter the way an object acts by calculating what size componant we need to achieve the desired result
so where does that leave my other understanding of componants?
Thanks again for explaining, have you ever had a student this tiring before **broken link removed**
edit: just read my post again, told you i had a short memory, so electrons don't move about on waveform, the waveform is purely a measurement tool
got house chores to do now so coming off computer for tonight, will be on phone later
Zener's (Zs) and IC type voltage regulators (VRs) perform similar functions, but in vastly different ways. And they don't "clip" power so much as control the level of the voltage by adjusting the voltage (for Zs) or adjusting voltage AND current (for VRs) available to a circuit (confusing, I know).
And yes, there are zeners than can handle large currents (50A, higher).
But I guess the easiest way to explain the difference between Zs and VRs is in the methods by which this is accomplished.
A zener is an adjunt to a load, that is to say, it is in a separate circuit (beside it, that is) from the load. It is drawing power (as current, limited by a resistor) that is parallel to the load. Changing the load affects the output of the zener (as you could see from the sims) because of current variations through the zener which in turn changes the voltage across the zener. Thus the zener displays a variation in it's "maintaned" voltage.
A Voltage Regulator, while in principle is doing the same thing, is in series with the load and is designed to maintain a more constant voltage level over a much broader range of varying load conditions.
So, a zener is used for a "fixed" load ( a bias, for instance, which is a constant load)) and a VR is for a "varying" load (what you have proposed with the distribution box). But they're both capable of handling varying (within limits) source level voltage inputs.
And the wider the variations in source voltage levels, all around, the greater that BOTH will experience heating issues. Throw in increasing loads on a VR and the heating issue grows considerably.
I've got the BASIC version (9.0) for (79 USD). It does not have a very sophisticated router routine. But it does have one.
But, generally speaking, for the simpler circuits (like what I mostly do), it suits me fine.
A good router pays for itself when you tackle microprocessor designs. Trace densities go through the roof and trying to do it by hand is virtually impossible. Nice, square trace corners are needed for professional results.
I looked this morning & thought posting at 2.51am **broken link removed** then relised that would be 21.51 in your time **broken link removed**
This is quite a big task for the odd hour here & there isn't it, I'm trying to spend time inbetween keeping up with normal jobs & finding information to help when I do get on here
ok, summing up so far, I feel like I have to have this understanding right so I can fully understand the way we will manipulate electric in whatever outcome we desire.
So the waveform I have read up on & understand it better, I hope **broken link removed** it is basically a rate of oscillation back & forth on AC that is measured in frequency
I have even read the diffence between how AC & DC is converted by an alternator/dynamo
Do you know, I never realised that AC works on magnetic force rather than brushes & now understand why you get that back an forth motion of AC
A transient is basically a quick fluctuation in circuit of either voltage or current
All those scary looking sums are just a means to calculate componant values & should actually make life easier when needing to work things out.
So, am I ready for componants now, please say yes **broken link removed**
So componant wise, I now need to understand the difference/meaning of what kiss was on about
Some clues are in the designations:
C (Capacitor) The voltage across a capacitor cannot change instantaneously.
L (Inductor) The current through an inductor cannot change instantaneously.
R Resistor The current and voltage across a resistor can change instantaneously
D Diode
Q (Some sort of semiconductor like a transistor)
So am right in thinking a capicitor smooths voltage out
an inductor smooths current out, both at a fixed value
but a resistor actually changes the value
a diode only lets current one way (generally, until you start looking at individual componants)
a semiconductor is some sort of switch to control either current or voltage
how am I doing so far **broken link removed**
that can't be right can it, because capicitors & inductors can still change the values, I must be overthinking this & it is just as kiss explained, so basically capicitors & inductors are some form of regulator/safety device compared to resistors being able to alter value but they cannot restrict overvoltage/current
That has to be right now doesn't it
edit: sorry, forgot to say 'morning' CBB **broken link removed**
Gotta get ready for work again now, this takes an age to understand doesn't it, that's took me a fortnight just to understand basic principle of electric, never mind, onwards & upwards **broken link removed**
I have even read the diffence between how AC & DC is converted by an alternator/dynamo
Do you know, I never realised that AC works on magnetic force rather than brushes & now understand why you get that back an forth motion of AC
A transient is basically a quick fluctuation in circuit of either voltage or current
All those scary looking sums are just a means to calculate componant values & should actually make life easier when needing to work things out.
So am right in thinking a capacitor smooths voltage out
an inductor smooths current out, both at a fixed value
but a resistor actually changes the value
a diode only lets current one way (generally, until you start looking at individual componants)
a semiconductor is some sort of switch to control either current or voltage
Yes. These are all true enough in a DC environment. And at the moment we're limiting our discussion to DC only.
But on that note, resistors have the same affect on DC as well as AC, but capacitors and inductors behave a lot differently in an AC environment. We can discuss that later once we work out the DC side of things.
as kiss explained, so basically capicitors & inductors are some form of regulator/safety device compared to resistors being able to alter value but they cannot restrict overvoltage/current[/QUOTE
Yes to the first part: "regulator/safety device compared to resistors", but no to the second part: "but they cannot restrict overvoltage/current". They can but again, more often in an AC environment and to a lesser extent a DC arena.
I remember that I had to figure out DC theory first before I was able to get even close to working out AC theory.
So hang in there. You'll get it.
You've done very well understanding what can be an enormously complex set of concepts, and in very short time.
Now stuck in park looking after big hole while plumber goes & gets parts as our ground lads have gone through water pipe, man it's cold
Glad my theory is getting there, feel like I can now get back to componants & yes it is very neat that you can change things
Edit: updating post 132 Inbetween work while waiting
lol. Yeah, wonderful, just started my locking up run :-(
It'll take about hour an half, it is now 6:50 & I normally try to get finished for 7:30......sigh
Never mind, looking forward to getting back to this
ok, I've never eaten tea so quick, so now I have a general understanding, where were we, I think we are ready to go back to the mini pcb **broken link removed** because as I cannot identify everything on the board, you know by now, that I just have to know, it would be nice to know each componant, why they are used on there & what it's doing & yes, I know it's only rated at 1A & isn't what I need, but hey, it can teach me something more than I know at the moment**broken link removed**
so where to start, is that gold & black componant a zener diode or switching diode
then we have three cream things that look like resistors but don't
R7, is that a 252 ohm /5% tolerance resistor?
R2, 202 ohm /5%
R1, 162 ohm /20% tolerance
same with a big white one (so is this a 22.4K ohm/5% tolerance resistor?) R4 on the board at bottom
then theres two black & silver things that look like recitfiers
feel free to step in here & help me out, as I haven't seen these componants before **broken link removed**
so, what have I learnt tonight, it is easier to make a board from scratch than to try & identify parts when your guessing what they are **broken link removed**
if those are all resistors, the more tolerance they have, the bigger they get
but gut feeling tells me they are not all resistors **broken link removed**
R4 ain't no resistor is it? & if I was being honest with myself I'm doubting R7 & R1 as well because they have a minute blue line at bottom of them
Please excuse me for being late. Had a hectic day and I am (at heart) lazy. But I have begun to decipher the board for a schematic BUT, it ain't ready yet...
1. so where to start, is that gold & black componant a zener diode or switching diode
2. then we have three cream things that look like resistors but don't
3. R7, is that a 252 ohm /5% tolerance resistor?
4. R2, 202 ohm /5%
5. R1, 162 ohm /20% tolerance
6. same with a big white one (so is this a 22.4K ohm/5% tolerance resistor?) R4 on the board at bottom
7. then theres two black & silver things that look like recitfiers
1. Yes
2. ALL of the thingys with colored stripes, flat or standing up, ([(except the black ones with a silver band) are resistors. The black/silver ones are diode/rectifiers.
3. R7 is a 2500 (2.5k) ohm resistor 1[SUP]st[/SUP] (Red=2, 2[SUP]nd[/SUP]green=5, 3[SUP]rd[/SUP]red [multiplier, 100]).
4. Probably 100 ohms (could be wrong. Hard to tell the first color) and same decode as in 3. above.
5. Hard to see, but my guess is an 1800 (1.8k) ohm.
Don't forget. First two colors are digits and the third is a multiplier:
black=1
brown=10
red=100
orange=1000
etc.
6. Looks like 2200 (2.2k) ohms with 1% tolerance.
Tolerance values are: NO 4[SUP]th[/SUP] band, 10%, Silver band, 5% and Gold band, 1%.
NOTE that the tolerance bands are separated a tad more from the first 2 or 3 bands that code the resistance value.
7. Yes.
Lastly:
if those are all resistors, the more tolerance they have, the bigger they get
The tolerance refers to the accuracy of the resistance value, i.e., how close to the rated value (by the color code) is the actual resistance likely to be. For close tolerance work, I always measure the resistor with an ohm meter first before I put it in the circuit. But, to be honest, I rarely need precision resistors. 5% or 10% is generally just fine (and cheaper).
On that note, the physical size of a resistor is a general indication of what sort of power (watts) it can dissipate (how much current it can handle before it literally burns up). Bigger size=bigger dissipation. R5 looks like 1/8 watt, while r7 looks like 1/4 watt and R4 1/2 watt.
With resistors there can be more than 4 bands (and fewer), especially with precision resistors.
Please excuse me for being late. Had a hectic day and I am (at heart) lazy. But I have begun to decipher the board for a schematic BUT, it ain't ready yet...
No need to apolagise for not being on here, thats the good things about forums, no matter what our time difference, it means we still get to talk **broken link removed**
I'm sure your having same problems as me with schematic, hard to tell parts from photos
OK, Let's start here.
1. Yes
2. ALL of the thingys with colored stripes, flat or standing up, ([(except the black ones with a silver band) are resistors. The black/silver ones are diode/rectifiers.
3. R7 is a 2500 (2.5k) ohm resistor 1[SUP]st[/SUP] (Red=2, 2[SUP]nd[/SUP]green=5, 3[SUP]rd[/SUP]red [multiplier, 100]).
4. Probably 100 ohms (could be wrong. Hard to tell the first color) and same decode as in 3. above.
5. Hard to see, but my guess is an 1800 (1.8k) ohm.
Don't forget. First two colors are digits and the third is a multiplier:
black=1
brown=10
red=100
orange=1000
etc.
6. Looks like 2200 (2.2k) ohms with 1% tolerance.
Tolerance values are: NO 4[SUP]th[/SUP] band, 10%, Silver band, 5% and Gold band, 1%.
NOTE that the tolerance bands are separated a tad more from the first 2 or 3 bands that code the resistance value.
7. Yes.
Lastly:
The tolerance refers to the accuracy of the resistance value, i.e., how close to the rated value (by the color code) is the actual resistance likely to be. For close tolerance work, I always measure the resistor with an ohm meter first before I put it in the circuit. But, to be honest, I rarely need precision resistors. 5% or 10% is generally just fine (and cheaper).
On that note, the physical size of a resistor is a general indication of what sort of power (watts) it can dissipate (how much current it can handle before it literally burns up). Bigger size=bigger dissipation. R5 looks like 1/8 watt, while r7 looks like 1/4 watt and R4 1/2 watt.
it was nice trying to see if I could work it out myself last night & great to be shown where I'm going wrong, guess you know by now I don't want to settle for achieveing something, I want to be able to understand it, & on that point, it looks like I've a way to go, I'm still putting decimal point in the wrong place **broken link removed**
I did use a colour band chart but when it said 3rd band was x100 I can see I was stil using the third band as a digit, after your explaination, it makes a lot more sense, I think your doing a grand job of getting me through all this **broken link removed**
Blinking heck, you've got good eyesight, I had to zoom photo right in, would it make it easier if I desolder this & two retifiers as it looks like they have numbers too **broken link removed**
As a rule of thumb, an 1/8[SUP]th[/SUP] watt resistor is about the diameter of a paint can spray tube. Not even that much, really. As you develop a pile of spare resistors, you'll recognize the 1/8[SUP]th[/SUP] watt ones as the smallest in the group. Any smaller than that and they'll probably be SM (surface mount) types, almost too tiny to manipulate without tweezers: I never use them.
Subsequent wattage sizes are generally proportional. Only the really big wattage resistors are marked with the wattage capacity, and then not often.
4pyros, you've got some impressive eyes there. The glasses I sometimes use these days for this kind of work look like night vision equipment.
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