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Culture / Music

Basics of electroacoustics

Understand the basics of sound reproduction.

Found 14 items

Adder is called a combinational digital device designed to execute the operation arithmeti-IC of adding numbers represented in binary codes. Adders are used in the operations of summation and subtraction of numbers, but also form the basis of multiplication and division of numbers. The principle of treatment of digits of numbers after distinguish-coherent and parallel adders. In the serial adders the addition of numbers is done bitwise, after thus, in parallel – all bits are processed simultaneously. The number of insights distinguish polyommatini one-bit adders and multi-bit adders. Polyommatini and single-bit adders. Adding two single-digit binary numbers is characterized by the addition table (a truth table), which reflects the values of the input...

A Demultiplexer (DMX or DMS) is called functional unit, which provides the transmission of digital information received on one line to several output lines. Selection of output line is done with the help of signals on the address inputs. Thus, the demultiplexer performs the conversion, reverse the action of the multiplexer. Similarly, multiplexers, demultiplexers are complete and incomplete. Consider the operation of the demultiplexer have the future four outputs, the state of its inputs and outputs are given in the table (Fig. 21.6 a). From this table follows: Y0 = D(A0A1); Y1 = D(A0A1); Y2 = D(A0A1); Y3 = D(A0A1). (21.2) ie realize such a device can, as shown in Fig. 21.6 b. To increase the number of outputs of the demultiplexer use the cascade connection...

The Multiplexer is a functional node that performs lausy connection (switching) of one of several WMOs-ing data to the output. The number of the selected entry corresponds to the code submitted to the address inputs of multiplexer. Similarly, decoders, multiplexers are complete and incomplete. The multiplexer has the information, the address inputs and, as a rule, allow (gate). The development chausie inputs used to extend the functionality of a multiplexer. They are used to increase the capacity of a multiplexer, synchronization with other nodes. The signals on the enable inputs can allow and can not allow you to connect a certain input to output, i.e., can block the action of the entire device. The multiplexers denoted as MUX (from the English...

At the output of the encoder (encoder) is set to binary code corresponding to decimal number initiated data input. In the callout boxes using the letters of the CD (from the English. Soder). The encoder can be used to represent (encode) a decimal number binary code and for issuing the specific code (the value pre-selected) when you press the corresponding symbol. When this code system is notified that a specific key is pressed on the keyboard. Fig. 20.5. Eight-bit decoder Similarly, the decoders, the encoders are complete and incomplete. For a complete encoder the condition n = 2 N , where n is the number of inputs, N is the number of outputs. Fig. 20.6. IC 155ID9 Fig. 20.7. Pair ID9 with led indicators To convert the code to the keypad in a four-digit...

A Decoder is called a Converter of a binary n-bit code in a unitary position 2n-bit code, all bits of which, except one, are equal to zero. De encoders are complete and incomplete. the full decoder the condition N = 2n, where n is the number of inputs, N is the number of outputs. If the decoder uses a partial number of outputs, the decoder is called incomplete. So, for example, a decoder with 4 inputs and 16 outputs, will be complete and with only 10 outputs is incomplete. In a symbol decoder uses the letters DC (from the English. Decoder). the inputs of the decoders are denoted by their binary weights. In addition to information inputs of the decoder has one or more of the inputs work, denoted as E (Enable). If you have permission on this input, the...

Digital logic devices are divided into two classes: combinational and posledovatelnostyu. Combinational digital devices implement various conversions of binary digital signals on the basis of combinational logic functions. The output signals of the com-bination devices at any time is uniquely determined by the input signals occurring in this mo-ment of time. the main types of such devices include adders, decoders and encoders, converters of codes, multiplexers and demultiplexers, charts comparison, binary numbers, etc. the Second logical device contains the sequential Celestia diagrams or finite state machines. The sequence-ing device necessarily include memory elements. Week-ends signals posledovatelnosti devices are determined not only by the signals...

Simultaneous bidirectional information transfer on a single cable. In the display VT100 (DEC) used scheme that allows to transmit information in two directions simultaneously from two independent and are not synchronized sources (Fig. 19.16). The schema contains two identical transceiver, a combined two-wire line L. In the table. 19.1 shows the four possible States of the device. The signals A, b, C and D are presented in table. 19.1 Booleans, the rest of the signals presented in the form of approximate values of voltages read more

The most Important task in the design and operation of electronic circuits is struggle against failures due to noise. Such interference can occur directly on printed circuit boards and signal transmission by cable. In cases where digital signals must be transmitted over the cable or between the measuring devices, there are specific problems. An important role plays the effects of capacitive loading on high-frequency signals, common-mode crosstalk as well as on "the effects of a long line" (reflections from mismatched load). Parasitic coupling of the digital elements of power circuits on vnutriplitnykh connections. A typical problem of occurrence of interference on the PCB is the presence of current pulses in the power supply circuit. read more

Using logic elements TTL and CMOS simply to control devices of the relay type, such as lamps or LEDs, Electromechanical relays, digital indicators, and even commuting the load in AC circuits. The main task is to harmonize the currents and voltages required for the discrete devices, with output parameters of digital circuits. There are three approaches to solving such tasks. The first is the use of IP output stages which are able to give the required signals, for example, to switch a high load current or high voltage. At small currents and voltages, for example, to control the led indicator (Fig.19.8,a) or low-power relay, load is connected directly to the active output. read more

Input signal from the mechanical keys. If you know the input characteristics of the driven logic circuit, it is pretty easy to manage digital inputs from switches, keyboard, Comparators, etc. it is easiest here to use a resistor connected to the power bus (Fig. 19.6 a). When working with elements of the TTL, taking into account their input characteristics, is better when the resistor is switched to ground. In this case, the key gives good dissipation current at low level input, and the resistor provides the high-level voltage of +5 V, creating a high noise immunity. In addition, it is convenient to have the reset circuit to ground through the key. read more

The most Important task in the design and operation of electronic circuits is struggle against failures due to noise. Such interference can occur directly on the printed PLA-tah, and the signal transmission cable. In cases where digital signals must be transmitted over the cable or between the measuring devices, there are specific problems. An important role plays the effects of capacitive loading on high-frequency signals, common-mode crosstalk as well as on "the effects of a long line" (reflections from mismatched load). Parasitic coupling of the digital elements of power circuits on vnutriplitnykh connections. A typical problem of occurrence of interference on the PCB is the presence of current pulses in the power supply circuit. read more

Using logic elements TTL and CMOS simply to control devices of the relay type, such as lamps or LEDs, Electromechanical relays, digital indicators, and even commuting the load in AC circuits. The main task is to harmonize the currents and voltages required for the discrete devices, with output parameters of digital circuits. There are three approaches to solving such tasks. The first is the use of IP output stages which are able to give the required signals, for example, to switch a high load current or high voltage. At small currents and voltages, for example, to control the led indicator (Fig.19.8,a) or low-power relay, load is connected directly to the active output. read more

Input signal from the mechanical keys. If you know the input characteristics of the driven logic circuit, it is pretty easy to manage digital inputs from switches, keyboard, Comparators, etc. it is easiest here to use a resistor connected to the power bus (Fig. 19.6 a). When working with elements of the TTL, taking into account their input characteristics, is better when the resistor is switched to ground. In this case, the key gives good dissipation current at low level input, and the resistor provides the high-level voltage of +5 V, creating a high noise immunity. In addition, it is convenient to have the reset circuit to ground through the key. read more

Electronic devices, working with both analog and digital signals have analog input and output blocks (amplifiers, filters, etc.), ADC and DAC digital blocks. However, there is often no need to use the full ADC or DAC, it is sufficient to associate a discrete device directly from a digital circuit. Such discrete devices may be devices input (switches, keypad, outputs, Comparators, etc.) and digital output (indicator lights, relays). Consider the questions of circuit characteristics of the various types of chips, pairing them with each other and external devices. Another urgent issue is the input and output of digital signals on circuit boards and external devices, and their transmission by cable. read more