Why we cannot use alternating current in telecommunication systems

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Why did the telephone come about as a semi-direct current system when one could have easily used the direct current that can be generated from a larger battery bank for the same distance? The answer to that question can be found by reading the writings of the great inventor Thomas Edison. Edison applied for a patent in 1887 on the direct current transmission of signals using alternating current (AC) for telegraph communication. His document clearly states that he wants to transmit signals that are much shorter than the full-length circuits and signals used in the public telegraph system at the time. He also adds that “The maximum amount of power available at a given point of transmission of communication is dependent upon the circuit and signal complexity and the circuit and signal signal characteristics of the transmitter”.

The average circuit size of an electric telegraph machine is usually a single 100-ampere line, plus an extension to connect to the local office. The average signal length of that circuit can be up to a mile in length and is designed for ten-minute signals. This is a fairly simple concept that all you have to understand to understand that alternating current cannot transmit signals that are more than tens of centimeters long at a distance of more than one or two miles. Even if the battery power is only 20 cents, the current could not exceed 5 amperes for that distance. Edison had intended the use of alternating current for automatic signal transmission to be the use of two wires for continuous transmission of signals of 500 to 1500 volts, with each wire running from a battery box to an antenna.

When alternating current was applied to telecommunication systems, the capacity of batteries was too low to accommodate the power needed to generate the initial power needed to generate the signals. It also became apparent that the batteries were not going to be able to sustain continuous operation. It was also not possible for the operators to quickly load and discharge batteries during periods of increased power consumption. As a result, alternating current was introduced for telegraph signals only on a short term basis in order to improve efficiency.

Today, it is common to have six to seven banks of batteries for communication systems. Because there is more capacity for battery power today than there was at the beginning of the electric telegraph system, some telecommunication systems can easily use direct current for long-distance transmission. The converter can be connected to the battery bank and then allow the voltage to be drawn from the battery bank during periods of low demand on the battery. This allows much longer transmission times of higher rates of communication. For example, if we were to use an AC generator to produce direct current (DC), then at the end of a week we could not load the battery banks to the level needed to generate the high rate of power required for a telecommunication system. If we did use DC generators instead, we would probably load the batteries to nearly the same level as if we used alternating current.

Converting to AC

At the time of Edison’s filing of the patent for telegraphic signals in 1887, the conversion from DC to an alternating current required about 14 volts of power to produce one kilowatt of AC power. In 1897, electric generators produced 500 to 700 volts. As time went on, with the improvements in electric power transmission, the voltage of generators increased, which decreased the amount of power needed to produce an AC current of a few hundred volts. Electric power companies were eventually able to convert their power systems to use 750 to 900 volts of power. Some even used 1,500 volts for short-term transmission of radio signals. We can translate this direct-current power system into DC power. This is an extremely simplified representation of what a system using direct-current power might look like today.

Converting from DC to AC

The battery bank that is installed in a telecommunication system is a relatively small component in this type of transmission. A battery bank uses a relatively small amount of power. Even in a long distance transmission system, a battery bank might only produce a small amount of power. Even if the battery bank is well-designed, it still only produces power between ten and twenty dollars per kilowatt of power. At those rates, the battery bank has a much smaller electrical load than the transmission system that is connected to it. Even a relatively low amount of power would be sufficient to generate a useful signal transmission for a low bandwidth communication system. If you build a system that has a transmission range of 10 to 20 miles, you can create a 50 to 100 kilowatt transmission system. At the rate of 500 kilowatts per mile, you can generate about five miles of signals. If we built a low-cost system and used low-quality electrical power, then we could generate a signal transmission system with a maximum range of 10 to 20 miles. The range of a low-cost system might be limited by where it is located. For example, if a transmission system is placed close to buildings, it might only be able to transmit signals a few hundred yards from the building.

At the distance that we are using the electrical grid for now, the electricity that we use is available to transmit at approximately 100 kilowatts per mile. For many years, the transmission system in our area was limited to approximately 400 kilowatts per mile. Within our electrical grid system, the transmission lines that go from the generating station to the transmission station are generally equipped with conductors that are rated between 1.5 and 1.8 kilowatts per mile. The transmission line is attached to a transmission station. At that point, the conductor is connected to a battery bank. The battery bank produces a sufficient amount of power to quickly charge the batteries of the transmission station, so that the transmission system is ready to transmit signals within about ten minutes. This charging process occurs in an alternating current system. Because the frequency of the alternating current has a constant frequency, the frequency of the frequency of the electrical grid varies with time. For this type of transmission system, the frequency of the electrical grid is approximately 50 cycles per second.

The transmission lines that connect to the transmission station are also 50 cycles per second. When the transmission lines are charged with current, they produce a low voltage wave on their surface, which causes the signals that are produced by the transmission system to reflect from the surface of the wires in a wave pattern. Because of this reflection, the power that is sent to the transmission station from the generation station can be shifted back and forth between low voltage and high voltage. This mechanism allows for a small amount of power to be transmitted from the generation station to the transmission station. At the transmission station, the wave patterns of the transmitting wires are reflected from a small capacitor in the wall. That makes the wave pattern of the transmission signal slightly modified. If you look at the wave pattern that is reflected back at you, you can usually see a slight shift in the frequency of the electrical grid. When the transmission line reflects from a capacitor in a wall, the wave patterns shift in a cycle between low and high voltage.

With a low voltage wave, the wave pattern of the transmission signal shifts between the high voltage and the low voltage. For most of the current power transmission system, the transmission lines are low voltage. They might be a little over 400 volts. At a certain transmission frequency, the transmission line gradually goes over to be high voltage. At that point, the transmission line is a little over 600 volts. When the transmission line is over 600 volts, the transmission lines are high voltage. At a certain frequency, the transmission line gradually goes over to be a little over 700 volts. At that point, the transmission line is a little over 800 volts. When the transmission line is over 800 volts, the transmission line has a medium voltage wave pattern. At a certain frequency, the transmission line gradually goes over to be a little over 900 volts. At this frequency, the transmission line is medium voltage. At that frequency, the transmission line is approximately 900 volts. At the frequency of the transmission system, the transmission line is approximately 900 volts. The wave patterns that are reflected back from the transmission line are at the low voltage frequency. That means that the wave patterns reflect from the transmission line at about 45 cycles per second.

A transmission system with a maximum range of 10 to 20 miles. For the transmission system that we are using in our neighborhood, the transmission system has a range of approximately 5 miles in either direction. By doubling the transmission system that we are using, we are extending the range of the transmission system in the direction of the grid and in the direction of the wind. For this type of transmission system, it is necessary to have the transmission system completely within the transmission system. If it is not within the transmission system, it is not transmitted. For this type of transmission system, the transmission line is high voltage. It is about 500 volts at the beginning of the transmission line. When it becomes low voltage, it is about 410 volts. After the transmission line becomes low voltage, it transitions to medium voltage. At that point, it is about 500 volts, but it is not entirely within the transmission system. At the maximum range of transmission system, the transmission line can be in a line within 5 miles in either direction.

After the transmission system becomes low voltage, the transmission line can transition to medium voltage. At that point, it is about 600 volts. After the transmission line becomes medium voltage, it transitions to low voltage. At this point, it is about 400 volts. After the transmission line transitions to low voltage, it is approximately 400 volts. For a transmission line that has a maximum range of 20 miles, a frequency of about 7.5 cycles per second, the transmission line is approximately 400 volts at each pole. If you were to draw a line that is 20 miles long to the pole, then you would have to be close to the poles to begin with to get over 400 volts. It is also necessary to be close to the poles to get more than 400 volts into a transmission line. At the maximum range of transmission system, the transmission line is approximately 300 volts at each pole. At the transmission station, the wave patterns of the transmitting wires are reflected from a small capacitor in the wall. That makes the wave patterns of the transmission signal slightly modified.

If you look at the wave patterns that are reflected back at you, you can see that there is a slight modification in the wave patterns that you are receiving. At this frequency of transmission, the transmission line is approximately 400 volts. After the transmission line transitions to medium voltage, it transitions to low voltage. At that point, it is approximately 400 volts. At this frequency of transmission, the transmission line is approximately 400 volts. At a certain frequency, the transmission line begins to transition from low voltage to medium voltage. At that frequency of transmission, the transmission line transitions from 400 volts to 600 volts. When the transmission line transitions from 600 volts to 700 volts, the transmission line transitions from medium voltage to high voltage. At this frequency of transmission, the transmission line transitions from 700 volts to 900 volts. The frequency of transmission line transitions from 700 volts to 900 volts.

If we were to draw the transmission line, we would have a frequency of about 40 cycles per second. If we were to increase the frequency of transmission line transitions to 60 cycles per second, the frequency of transmission line transitions would be approximately 50 cycles per second. At this frequency, the transmission line has a frequency of about 40 cycles per second. After the transmission line transitions to 900 volts, the transmission line transitions to low voltage. At this frequency of transmission line transitions, it transitions from 900 volts to 500 volts. At this frequency, the transmission line transitions from 500 volts to 400 volts. At this frequency of transmission line transitions, the transmission line transitions from 400 volts to 300 volts. At this frequency of transmission line transitions, it transitions from 300 volts to 180 volts. At this frequency of transmission line transitions, it transitions from 180 volts to 220 volts. When the transmission line transitions from 220 volts to 170 volts, the transmission line transitions from low voltage to medium voltage. At this frequency of transmission line transitions, it transitions from 600 volts to 400 volts. At this frequency of transmission line transitions, the transmission line transitions from 400 volts to 200 volts.

The frequency of transmission line transitions is at least 60 cycles per second and at least 60 cycles per second. From what I could tell, the frequency of transmission line transitions is approximately 50 cycles per second. For a transmission line with a transmission line that has a maximum range of 20 miles, the frequency of transmission line transitions is approximately 400 volts. It is also necessary to be close to the poles to begin with to get over 400 volts into a transmission line. At this frequency of transmission, the transmission line is approximately 300 volts. At the transmission station, the wave patterns of the transmitting wires are reflected from a small capacitor in the wall. That makes the wave patterns of the transmission signal slightly different from the wave patterns that you are receiving.

The interference of the wave patterns that you are receiving from the transmitting wires causes some fluctuations in the wave patterns that you are receiving. At this frequency of transmission, the transmission line transitions from 300 volts to 200 volts. At this frequency of transmission, the transmission line transitions from 200 volts to 150 volts. After the transmission line transitions to 150 volts, the transmission line transitions from 150 volts to 100 volts. When the transmission line transitions from 100 volts to 40 volts, it transitions from low voltage to medium voltage. When the transmission line transitions from 40 volts to 30 volts, the transmission line transitions from low voltage to medium voltage. At this frequency of transmission line transitions, the transmission line transitions from medium voltage to high voltage. At this frequency of transmission line transitions, the transmission line transitions from high voltage to low voltage. At this frequency of transmission line transitions, it transitions from low voltage to medium voltage.

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