
Photovoltaic transducers has been widely used in medical, consumer, scientific instrumentation, and industrial applications. Photovoltaic sensors is a solid-state devices and available for wide range of wavelength response, cover from infrared, visible, and ultraviolet spectrum. This characteristic make this type of transducer applicable in diverse jobs such as colorimetry, chemical spectral analysis, non-contact thermometry, non-invasive [...]
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This pin diagram will be useful when viewing these connectors. Sometimes you hold a soldering iron to the back of the connector, and you don’t remember the numbering of the pin. Here is the pin diagram for your reference: The number of each pins are actually stamped on both sides of any D-type [...]
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Notch filter is known as band-cut filter or band-reject filter. The fuction of this filter is to remove some frequency portion of a signal. The schematic diagram of this filter circuit, a second order notch filter is depicted in the figure below. The formula is actually complicated, but by taking the R3=R4 and [...]
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Using a single supply quad comparator LM339, LM239, LM2901, LM2901V, NCV2901, or MC3302, we can build a square-wave oscillator with simple circuit and formula. Here is the schematic diagram: This circuit is suitable if you need many square-wave oscillators in one circuit, since the quad packaged comparator provide four comparators in one single [...]
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The excellent high input impedance, high slew rate, and high voltage qualities of CA3140 op-amp make it suitable for Wien-bridge sine wave oscillator. The basic circuit for Wien-bridge sine wave oscillator is shown in the figure below (the upper part). You can see the formula in the figure, when R1=R2=R, and C1=C2=C, then the formula [...]
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This circuit is similar to our previous tone control circuit, a bass-treble tone control circuit, but here we present the formula for design your tone control’s custom frequency response. Here is the schematic diagram and formula of the tone control circuit: Almost all op-amp type can be used, as long as they have [...]
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