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NE612
The NE612 is an integrated circuit for processing of signals, such as in the transmission of radio signals. It consists of an oscillator and a mixer. (122 kB) It can handle signal frequencies of up to 500 MHz and local oscillator frequencies of up to 200 MHz. The mixer is a “Gilbert cell” multiplier configuration which provides both a gain of 14 dB and a noise figure of at 45 MHz. The IC belongs to a family of the following ICs: NE602, SA602, NE612 and SA612. It is widely used in amateur radio applications, e.g. in the commercial Elecraft Elecraft, Inc. is an American manufacturer of amateur radio equipment and kits based in Watsonville, California. It was founded in 1998 by Wayne Burdick and Eric Swartz. The company's first product was the K2 transceiver, first prototyped i ... products, and others. References Linear integrated circuits Electronic oscillators {{Electronics-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Local Oscillator
In electronics, the term local oscillator (LO) refers to an electronic oscillator when used in conjunction with a Frequency mixer, mixer to change the frequency of a signal. This frequency conversion process, also called Heterodyne, heterodyning, produces the sum and difference frequencies from the frequency of the local oscillator and frequency of the input signal. Processing a signal at a fixed frequency gives a radio receiver improved performance. In many receivers, the function of local oscillator and mixer is combined in one stage called a "Pentagrid converter, converter" - this reduces the space, cost, and power consumption by combining both functions into one active device. The term ''local'' refers to the fact that the frequency is generated within the circuit and is not reliant on any external signals, although the frequency of the oscillator may be tuned according to external signals. Applications Local oscillators are used in the superheterodyne receiver, the most c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gilbert Cell
In electronics, the Gilbert cell is a type of frequency mixer. It produces output signals proportional to the product of two input signals. Such circuits are widely used for frequency conversion in radio systems. The advantage of this circuit is the output Electric current, current is an accurate multiplication of the (differential) base currents of both inputs. As a mixer, its balanced operation cancels out many Parasitic oscillation, unwanted mixing products, resulting in a "cleaner" output. Gilbert cells can also be used as Variable-gain amplifier, variable-gain amplifiers (VGA). It is a generalized case of an early circuit first used by Howard Jones in 1963, invented independently and greatly augmented by Barrie Gilbert in 1967. It is a specific example of "translinear" design, a current-mode approach to analog circuit design. The specific property of this cell is that the differential output current is a precise Product (mathematics), algebraic product of its two differential ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analog Multiplier
An analog multiplier is an electronic circuit that produces an output level that is the mathematical product of the levels of its two analog signal inputs. Such circuits may be used to implement related functions such as ''squares'' by applying the same signal to both inputs, and ''square roots''. Types Electronic analog multipliers are classified by their function. A single-quadrant multiplier permits only one, typically positive, level on the inputs. A two-quadrant multiplier permits one input signal to swing to positive and negative levels, while the second input remains positive. In a all inputs may swing to positive or negative levels, producing a positive or negative output level. Voltage-controlled amplifier If one input of an analog multiplier is held at a steady voltage, a signal at the second input is scaled in proportion to the level on the fixed input. This may be considered a voltage-controlled amplifier or variable-gain amplifier. Applications are for electroni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decibel
The decibel (symbol: dB) is a relative unit of measurement equal to one tenth of a bel (B). It expresses the ratio of two values of a Power, root-power, and field quantities, power or root-power quantity on a logarithmic scale. Two signals whose level (logarithmic quantity), levels differ by one decibel have a power ratio of 101/10 (approximately ) or root-power ratio of 101/20 (approximately ). The strict original usage above only expresses a relative change. However, the word decibel has since also been used for expressing an Absolute scale, absolute value that is relative to some fixed reference value, in which case the dB symbol is often suffixed with letter codes that indicate the reference value. For example, for the reference value of 1 volt, a common suffix is "#Voltage, V" (e.g., "20 dBV"). As it originated from a need to express power ratios, two principal types of scaling of the decibel are used to provide consistency depending on whether the scaling refer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amateur Radio
Amateur radio, also known as ham radio, is the use of the radio frequency radio spectrum, spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency, emergency communications. The term ''"radio amateur"'' is used to specify ''"a duly authorized person interested in radioelectric practice with a purely personal aim and without wikt:pecuniary, pecuniary interest"'' (either direct monetary or other similar reward); and to differentiate it from commercial broadcasting, public safety (police and fire), or two-way radio professional services (maritime, aviation, taxis, etc.). The amateur radio service (''amateur service'' and ''amateur-satellite service'') is established by the International Telecommunication Union (ITU) through their recommended radio regulations. National governments regulate technical and operational characteristics of transmissions and issue individual station li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elecraft
Elecraft, Inc. is an American manufacturer of amateur radio equipment and kits based in Watsonville, California. It was founded in 1998 by Wayne Burdick and Eric Swartz. The company's first product was the K2 transceiver, first prototyped in October 1997. Products The company is known for the Elecraft K3 high-performance HF transceiver, a 32-bit DSP based radio covering HF plus the 6-meter VHF band and the 160-meter MF band, introduced in 2008. The K3 was well-received by the amateur radio community. At the time of its introduction, the K3 ranked highest in Sherwood Engineering's receiver tests. Elecraft's product lineup includes QRP CW transceivers, the K2 and K3 all-mode 100 W transceivers, KX2 (80m-10m) and KX3 (160m–2m) portable transceivers, linear power amplifiers, panadapters, and accessories including antenna tuners and signal generators. Elecraft introduced "mechanical assembly only" (or " no solder") kits with the K3 line of products, allowing enthu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linear Integrated Circuits
In mathematics, the term ''linear'' is used in two distinct senses for two different properties: * linearity of a '' function'' (or '' mapping''); * linearity of a ''polynomial''. An example of a linear function is the function defined by f(x)=(ax,bx) that maps the real line to a line in the Euclidean plane R2 that passes through the origin. An example of a linear polynomial in the variables X, Y and Z is aX+bY+cZ+d. Linearity of a mapping is closely related to '' proportionality''. Examples in physics include the linear relationship of voltage and current in an electrical conductor (Ohm's law), and the relationship of mass and weight. By contrast, more complicated relationships, such as between velocity and kinetic energy, are ''nonlinear''. Generalized for functions in more than one dimension, linearity means the property of a function of being compatible with addition and scaling, also known as the superposition principle. Linearity of a polynomial means that its degree ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
