The function generator is capable of generating fundamental waveforms such as

The function generator is capable of generating

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of electronic test equipment. The function generator is capable of generating fundamental waveforms such as sine waves, triangular waveforms, and square waveforms. The voltage, symmetry, and time characteristics of a waveform can be adjusted to meet a specific application. 02/13/18 13
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A logic probe contains LEDs that produce a visual indication of what is occurring at a specific point in a digital circuit. It can indicate a high, low, clock, or lack of a signal. It can be used with a logic pulser, which looks similar to the logic probe. The pulser injects a logic level into a circuit, which can be picked up by the logic probe. The logic probe is useful for checking signals of various input and output pins of a circuit or an IC. 02/13/18 14
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Soldering Soldering is the joining of two pieces of metal alloy having a melting point below 800° Fahrenheit. Solder includes a combination of tin and lead. Tin-lead solder ranges from pure tin to pure lead and all proportions in between. In electrical soldering, the alloy mix is usually 60% tin and 40% lead (60/40) or 63% tin and 37% lead (63/37) For soldering surface mounted devices, a solder is available with 62% tin, 28% lead and 2% silver (62/36/2). Flux helps the solder alloy flow around the connections. Flux cleans the component leads of oxide and film, allowing the solder to adhere. Soldering flux is usually included in the solder in the central core. It also decrease the melting point of Solder. Rosin flux is always used in electrical soldering because it is noncorrosive. 02/13/18 15
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Characteristics of alloys of Tin and Lead are Plotted against Temperature 02/13/18 16
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Characteristics of alloys of Tin and Lead are Plotted against Temperature This graph allows one to see that only an alloy of 63/37 has a eutectic point (a single melting point). All other combinations start melting at one temperature, pass through a plastic stage, and then become a liquid at a higher temperature. Any physical movement of the components being soldered while the solder is in the plastic stage will result in a fractured solder connection. Such a connection will appear dull and grainy, and is mechanically weaker and less reliable. Therefore, 63/37 or 60/40 solder is commonly used in electronics because it does not remain in the plastic stage very long. 02/13/18 17
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Soldering Iron The primary tool used for installing, removing, and/or replacing components on a printed circuit board is the soldering iron. An improper choice in selecting a soldering iron or soldering iron tip may result in damage to the component and/or the printed circuit board. Select only a low wattage pencil soldering iron with an appropriate tip for the soldering being done. Solder guns are inappropriate for printed circuit board fabrication The soldering iron is usually specified by wattage. In most situations a 25- to 35-watt soldering iron is adequate. Wattage means the amount of heat capacity available at the tip. Iron-clad tips are the best selection for soldering printed circuit boards. An unplated tip will provide better heat transfer but wears rapidly and requires frequent cleaning and tinning. The iron-clad tip requires only an occasional cleaning and tinning.
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