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I'm willing to give anyone a freebie for a first shot. I was even trying to teach walters/markphaser at first back in the day.
So, playing straight man:
No. Signals do not have an impedance themselves. This refers to the fact that the impedance of a capacitor is Xc = 1/(2*pi*F*C) and the impedance of an inductor is Xl = 2*pi*F*L. So the impedance of a capacitor goes down as the signal frequency goes up, the impedance of an inductor goes up as frequency goes up. Why this happens is the subject of a semester or two of physics.
The cathode and anode are "charged" by an external voltage source, like a battery. With the battery (+) connected to the anode and the battery (-) connected to the cathode, any electrons boiled off the cathode are attracted to the (+) voltage on the anode, so a current flows. The phrase "charged with" implies something outside the tube doing the charging. Without that, nothing happens.
The battery acts like an electrical pump, sucking in electrons at the (+) end and pushing them out the (-) end, with a "pressure" equal to the battery voltage.
A signal may be a current, a voltage, or the interrelated movement of a current and a voltage at the same time. Signals are actually **information**, and that information is encoded as a presence/absence or variation of current, or the presence/absence or variation of voltage. Signals (that is, information) may be encoded many different ways. Current is not signal, voltage is not signal, but they may be used to transmit a signal, just like American Indians used smoke signals to carry infomation.
Yes, the guitar makes a signal whether or not the amp is on. If a tree falls in the forest and there is no one there to hear it, does it still make a noise? Of course it does.
This completes an electrical circuit allowing a battery or other power supply to start pumping electrons in the circuits. These power supplies have ony a certain maximum voltage "pressure" and if the switch is insulating enough to prevent that pressure from forcing current through it, the device does not work. When the switch allows current through, the device becomes activated.
No. "Diaphram" refers to only the part that moves the air. "Speaker Cone" is a loosely defined term, usually indicating the diaphram, the voice coil and other parts that hook it up to the speaker basket/frame. "Driver" is a generic word for "speaker" or just the speaker part of a horn.
No.
If I use a machine to pile up electrical charge on an object, the object has an electrical field as a result. This is YOU when you walk across a carpet in dry air and have static electricity spark from your finger to something else. Static (literally "not moving") electricity has an electrical field but no magnetic field. And changing voltages have changing electrical fields but no magnetic fields if no current is flowing.
If current flows, there is a magnetic field generated as a result of the current flow. There may or may not be a voltage involved in getting this current to flow.
When you have both a changing voltage and a changing current, you get a changing electrical field AND a changing magnetic field. This combined electrical and magnetic field may radiate into space as a self-supporting electromagnetic (or radio) wave. Getting conditions just right to get this electromagnetic field to radiate away is what antennas are about. Antennas match the circuit impedance to the impedance of free space so some of the energy in the circuit can escape into free space more easily.
So the paragraphs are not contradictory - they are complexly interrelated.
8) Title : Usage Of Capacitors
“Power Supply Smoothing : This is the easiest and very widely used application of a capacitor. If you stick a big beefy electrolytic capacitor (the bigger the better), it will fill in all the gaps created by rectifying an AC form, to create a relatively smooth DC. It works by repeatedly charging during the peaks, and discharging during the gaps. However, the more load you put on it, the quicker it wil drain the capacitor and the more ripple you’ll get”
8.1) Why there are gaps and peaks whilst rectification?
Read "Power Supplies Basics" at geofex.com.
But even more simply, to get DC out of AC, you have to use rectifiers. Rectifiers allow current to flow only one direction. While the diode is allowing current to flow from an AC source to a load, the voltage which gets to the load is much the same shape as the AC waveform, so there is a low start, high middle, and low ending to each half cycle. This leaves peaks, and gaps between them. Caps store energy up to the peak, then leak it out to the load until the next peak, smoothing over the valley.
Well, it's more complicated than that. A resistor allows a current to flow when there is a voltage across it. We know this as Ohm's law: V = I*R, or I = V/R. If you supply a voltage V to a capacitor C through a resistor R, then the instant you connect them, the voltage across R is V, because the cap is at 0V. So a current of I = V/R flows. But the capacitor stores the current as I = C dv/dt, or dv= I/C*dt. So the cap voltage rises, and that leaves less voltage across the resistor, and the current in the resistor goes down.
This is a classical first semester physics item. The voltage on the cap rises by 1/e for each time constant of R*C seconds after you do the math.
These two items are true only for the instants of starting a charge and ending a charge. In between is ..., well, in between.
As above. I = V/R I = Cdv/dt => dv/dt = V/R*C, so you must do the integral to come out with a time varying expression for dv/dt.
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Capacitors store charge. In fact, capacitance is *defined* as the ratio of the charge stored to the voltage it creates, or C = Q/V.
This brings up an interesting point: when is a capacitor "charged"? There is no universal end point. Charged has to mean "has all the voltage that the external electrical pump can pump in". So "charged" has to mean that there is no more voltage/current to put in, so no changes are happening.
By definition, "AC" means that signal is continuously changing, so by its very nature, AC **can not** charge a cap to completion. It's always changing. So AC will flow.
So, playing straight man:
1) Title : Signals
I read that “Impedance depends on Frequency Of Signals” What does that mean? Do Signals have Impedance in themselves?
I read that “Impedance depends on Frequency Of Signals” What does that mean? Do Signals have Impedance in themselves?
2) Title : Tubes
It’s said Cathode is charged with “-“ and Anode is charged with “+”. When filament is heated electrons flow from cathode to anode. When this movement is done cathode should be charged with “+” and anode should be charged is “–“ Isn’t it?
It’s said Cathode is charged with “-“ and Anode is charged with “+”. When filament is heated electrons flow from cathode to anode. When this movement is done cathode should be charged with “+” and anode should be charged is “–“ Isn’t it?
It’s said then electrons in the anode go “-“ terminal and after that “+” terminal of the battery. When the anode is charged with “-“ how those electrons go “-“ terminal of the battery? (Because “-“ push “-“)
3) Title : Signals
Are Current and Signals the same thing? How does current include information about signals in it?
Are Current and Signals the same thing? How does current include information about signals in it?
4) Title : Amps
When the amp is off does an electric guitar still send signals to the amp when played?
When the amp is off does an electric guitar still send signals to the amp when played?
5) Title : Electricity
How are Electrical devices activated when we pushed the “on” button?
How are Electrical devices activated when we pushed the “on” button?
6) Title : Speakers
Are diaphragm, speaker cone and the driver the same thing?
Are diaphragm, speaker cone and the driver the same thing?
7) Title : Electric And Magnetic Field
“Therefore, they are inter-related in a field called the electromagnetic field. In this field, the electric field and the magnetic field move at right angles to each other However, they are not dependant on each other. They may also exist independently. Without the electric field, the magnetic field exists in permanent magnets and electric fields exist in the form of static electricity, in absence of the magnetic field.”
“Wherever there is electricity, there also electric and magnetic fields, invisible lines of force created by the electric charges. Electric fields result from the strength of the charge while magnetic fields result from the motion of the charge, or the current.”
These two paragraph contradict each other? Don’t they?
“Therefore, they are inter-related in a field called the electromagnetic field. In this field, the electric field and the magnetic field move at right angles to each other However, they are not dependant on each other. They may also exist independently. Without the electric field, the magnetic field exists in permanent magnets and electric fields exist in the form of static electricity, in absence of the magnetic field.”
“Wherever there is electricity, there also electric and magnetic fields, invisible lines of force created by the electric charges. Electric fields result from the strength of the charge while magnetic fields result from the motion of the charge, or the current.”
These two paragraph contradict each other? Don’t they?
If I use a machine to pile up electrical charge on an object, the object has an electrical field as a result. This is YOU when you walk across a carpet in dry air and have static electricity spark from your finger to something else. Static (literally "not moving") electricity has an electrical field but no magnetic field. And changing voltages have changing electrical fields but no magnetic fields if no current is flowing.
If current flows, there is a magnetic field generated as a result of the current flow. There may or may not be a voltage involved in getting this current to flow.
When you have both a changing voltage and a changing current, you get a changing electrical field AND a changing magnetic field. This combined electrical and magnetic field may radiate into space as a self-supporting electromagnetic (or radio) wave. Getting conditions just right to get this electromagnetic field to radiate away is what antennas are about. Antennas match the circuit impedance to the impedance of free space so some of the energy in the circuit can escape into free space more easily.
So the paragraphs are not contradictory - they are complexly interrelated.
8) Title : Usage Of Capacitors
“Power Supply Smoothing : This is the easiest and very widely used application of a capacitor. If you stick a big beefy electrolytic capacitor (the bigger the better), it will fill in all the gaps created by rectifying an AC form, to create a relatively smooth DC. It works by repeatedly charging during the peaks, and discharging during the gaps. However, the more load you put on it, the quicker it wil drain the capacitor and the more ripple you’ll get”
8.1) Why there are gaps and peaks whilst rectification?
But even more simply, to get DC out of AC, you have to use rectifiers. Rectifiers allow current to flow only one direction. While the diode is allowing current to flow from an AC source to a load, the voltage which gets to the load is much the same shape as the AC waveform, so there is a low start, high middle, and low ending to each half cycle. This leaves peaks, and gaps between them. Caps store energy up to the peak, then leak it out to the load until the next peak, smoothing over the valley.
“Timing : If you supply power to a capacitor through a resistor, it will take time to charge.
This is a classical first semester physics item. The voltage on the cap rises by 1/e for each time constant of R*C seconds after you do the math.
If you connect a resistive load to a capacitor, it will take time to discharge. The key thing to understand here about timing circuits is that capacitors appear as though they are shor circuit while they are charging, but as soon as they are charged, they appear to be open circuit.”
8.2) How do capacitors do the Timing job?
“Filtering : If you pass DC through a capacitor, it will charge and then block any further current from flowing. However, if you pass AC through a capacitor, it will flow. How much current flows depends on the frequency of the AC, and the value of the capacitor.
A filter capacitor is an electronic component that removes voltage or signal spikes in electronic circuits. Capacitors are used as filter devices due to their ability to absorb and effectively store electrical charges at predetermined values.”
8.3) When capacitors are charged don’t they transmit the current?
A filter capacitor is an electronic component that removes voltage or signal spikes in electronic circuits. Capacitors are used as filter devices due to their ability to absorb and effectively store electrical charges at predetermined values.”
8.3) When capacitors are charged don’t they transmit the current?
Capacitors store charge. In fact, capacitance is *defined* as the ratio of the charge stored to the voltage it creates, or C = Q/V.
This brings up an interesting point: when is a capacitor "charged"? There is no universal end point. Charged has to mean "has all the voltage that the external electrical pump can pump in". So "charged" has to mean that there is no more voltage/current to put in, so no changes are happening.
By definition, "AC" means that signal is continuously changing, so by its very nature, AC **can not** charge a cap to completion. It's always changing. So AC will flow.
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