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The Geometrical Theory and of Diffraction Applied to
The Geometrical Theory and of Diffraction Applied to

... screen has a radius of three wavelengths and the monopole is a quarter wavelength long. It may be observed that there is good agreement betweenthe measured and calculated patterns, especially in the periodicity of the interferingsignalsand also in the pattern amplitude near 0 = 90'. However, in the0 ...
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around - QRQcw

Slide 1
Slide 1

ECE 206L - ecelabs
ECE 206L - ecelabs

ee221_3
ee221_3

... The passband of the filter refers to a range of frequencies that pass through the filter relatively unimpeded. The stopband of the filter refers to a range of frequencies that pass through the filter with relatively strong attenuation. The cut-off frequency refers to a frequency that determines the ...
alternating current
alternating current

... A transformer with 3000 turns in its primary coil is used to change an alternating pd from ac rms value of 240 V to ac rms value 12 V. When a 60 W, 12 V lamp is connected to the secondary coil, the lamp lights at normal brightness and a rms current of 0.26 A passes through the primary coil. ...
Electronics and Circuit lab Fall 2016 Egr110
Electronics and Circuit lab Fall 2016 Egr110

... Electricity is a natural occurrence that takes place in nature. For this lab we will focus on the electricity that powers our homes, devices and tools. Electric current is defined as the flow of an electrical charge, which can consist of any moving charged particles, most commonly these are electron ...
Document
Document

... are marked with dots or some similar system to indicate polarity. However. There is no standard system of marking transformers. nor will all transformers marked in any manner. In such cases the test circuit may be used to check the phase relationship. The transformers are connected in phase if the a ...
Design and Characterization of a QLUT in a Standard CMOS Process
Design and Characterization of a QLUT in a Standard CMOS Process

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...  A device used to measure current is called an ammeter  A device used to measure voltage is called a voltmeter  To measure the current, the ammeter must be placed in the circuit in series  To measure the voltage, the voltmeter must be wired in parallel with the component across which the voltage ...
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Why Things Don`t Work – Why S/N Theory Often Seems to be

Power Received by a Small Antenna
Power Received by a Small Antenna

... the load resistance to R = 108 Rrad. For a coil with N = 100 turns and the above l and r the radiation resistance is Rrad ≈ 1.5 × 10−4 Ω, so the load resistance should be R ≈ 15 kΩ.9 If it were desired for the AM radio to extract the maximum possible power from the wave, perhaps for a crystal radio ...
AdvLessons#11
AdvLessons#11

Question bank of physics - Kendriya Vidyalaya SAC, Vastrapur
Question bank of physics - Kendriya Vidyalaya SAC, Vastrapur

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Thursday, Dec. 1, 2011

... • What happens when an emf is applied to an inductor? – An inductor has some resistance, however negligible • So an inductor can be drawn as a circuit of separate resistance and coil. What is the name this kind of circuit? LR Circuit ...
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Advanced Circuits

... Introduction: Have you ever touched an incandescent light bulb that has been on for a while? Ouch! What you feel is frictional heat produced by the current moving through the light’s resistor. The high heat produced in electric circuits leads to the danger of electrical fires. A fuse is a safety dev ...
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Design of an electronic barometer

315MHz/433MHz ASK Superheterodyne Receiver with Extended Dynamic Range General Description Features
315MHz/433MHz ASK Superheterodyne Receiver with Extended Dynamic Range General Description Features

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Science 9 - Rocky View Schools

... 1. Go to the OHM zone web site. (http://www.article19.com/shockwave/oz.htm). This is an interactive web site that allows you to build your own circuits by dragging and dropping different components into the circuit board. 2. Make a circuit that has one battery, a switch, a light, and conductors conn ...
Basic Circuit Measurements (CIR)
Basic Circuit Measurements (CIR)

MS Word format
MS Word format

ALIGNMENT DATA T/S vs
ALIGNMENT DATA T/S vs

... The phase is constant throughout this period with a phase shift less than 5 throughout its bandwidth to 125Hz. The impedance phase does not cross the zero marker throughout a 125 Hz bandwidth with a single zero crossing occurring at driver resonance vs. 4 crossings for the T/L alignment. Driver ou ...
Circuits - Cathkin High School
Circuits - Cathkin High School

... Capacitors can introduce a time delay into electronic circuits due to the time they take to charge.  Tuning Capacitors are used when tuning into a radio station as part of the resonance circuit in a radio.  Blocking d.c. but allowing a.c. to pass A capacitor has infinite resistance to direct curre ...
Document
Document

Specification Number: 16410-5
Specification Number: 16410-5

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Crystal radio



A crystal radio receiver, also called a crystal set or cat's whisker receiver, is a very simple radio receiver, popular in the early days of radio. It needs no other power source but that received solely from the power of radio waves received by a wire antenna. It gets its name from its most important component, known as a crystal detector, originally made from a piece of crystalline mineral such as galena. This component is now called a diode.Crystal radios are the simplest type of radio receiver and can be made with a few inexpensive parts, such as a wire for an antenna, a coil of copper wire for adjustment, a capacitor, a crystal detector, and earphones. They are distinct from ordinary radios as they are passive receivers, while other radios use a separate source of electric power such as a battery or the mains power to amplify the weak radio signal so as to make it louder. Thus, crystal sets produce rather weak sound and must be listened to with sensitive earphones, and can only receive stations within a limited range.The rectifying property of crystals was discovered in 1874 by Karl Ferdinand Braun, and crystal detectors were developed and applied to radio receivers in 1904 by Jagadish Chandra Bose, G. W. Pickard and others.Crystal radios were the first widely used type of radio receiver, and the main type used during the wireless telegraphy era. Sold and homemade by the millions, the inexpensive and reliable crystal radio was a major driving force in the introduction of radio to the public, contributing to the development of radio as an entertainment medium around 1920.After about 1920, crystal sets were superseded by the first amplifying receivers, which used vacuum tubes (Audions), and became obsolete for commercial use. They, however, continued to be built by hobbyists, youth groups, and the Boy Scouts as a way of learning about the technology of radio. Today they are still sold as educational devices, and there are groups of enthusiasts devoted to their construction who hold competitions comparing the performance of their home-built designs.Crystal radios receive amplitude modulated (AM) signals, and can be designed to receive almost any radio frequency band, but most receive the AM broadcast band. A few receive shortwave bands, but strong signals are required. The first crystal sets received wireless telegraphy signals broadcast by spark-gap transmitters at frequencies as low as 20 kHz.
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