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1.1 Single-phase power supplies
1.1 Single-phase power supplies

... spectrum given in Fig Voltage source inverter drives (such as PWM-type drives) can have much higher distortion levels as shown in Fig. The input to the PWM drive is generally designed like a three-phase version of the switch-mode power supply in computers. The rectifier feeds directly from the ac bu ...
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DIY Kit 125 - NEGATIVE ADJUSTABLE POWER SUPPLY
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Oscillations and resonance in LC and LCR circuits
Oscillations and resonance in LC and LCR circuits

//////////////////////\/\/<<(E
//////////////////////\/\/<<(E

... of it without departing from the spirit and scope of the d. means external to the device for rapidly charging present invention. For example, it may be desirable to 10 the resonant device. shape the lamp 24 so as to'?ll substantially the entire ~ 2'. The light source according to claim 1 wherein the ...
using only two transistors
using only two transistors

... a simple oscillator. Figure 2 shows for comparison a well-known RF oscillator design. The simple oscillator keeps the amplitude of its output constant. We now modify the circuit so that the amplitude of the oscillations is much greater, and so that the transistor can be switched fully off. The value ...
Impulse voltage and harmonic voltage distortion tests for the
Impulse voltage and harmonic voltage distortion tests for the

Pulse Discharge Presentation
Pulse Discharge Presentation

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1- Harmonic Sources from Commercial Loads
1- Harmonic Sources from Commercial Loads

Solution to 1988B3
Solution to 1988B3

... (E) It is the same as the capacitance of each capacitor In series, the equivalent capacitance is calculated using reciprocals, like resistors in parallel. This results in an equivalent capacitance smaller than the smallest capacitor. ...
High Voltage Power Supplies for Analytical Instrumentation
High Voltage Power Supplies for Analytical Instrumentation

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PN-250CG SS Plug-In Solid-State Code Transmitter
PN-250CG SS Plug-In Solid-State Code Transmitter

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CH26 LAB Capacitors
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... knowing the geometry of the device. For most practical devices, the capacitor consists of capacitor plates which are thin sheets of metal separated by a dielectric, insulating material. For this reason, the schematic symbol of a capacitor is has two vertical lines a small distance apart (representin ...
Proposed System
Proposed System

Complicated Circuits
Complicated Circuits

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1 - Portal UniMAP
1 - Portal UniMAP

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New SOT Package Supervisors

Review_Exam2_ANS
Review_Exam2_ANS

... Answer: No. The capacitance of a capacitor is fixed by its size and shape. C = Q / V is a constant ratio for a given capacitor: if Q increases, V increases so that the ration Q / V remains constant. RII-3. A capacitor is attached to a battery which maintains a constant voltage V across the capacitor ...
Chapter 18 – DC Circuits
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I www C?.
I www C?.

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... 1. a. Construct the circuit shown in Figure 1 below using a 1-µF capacitor for C1. Use the LCR meter to determine a "good" value for the capacitance. Next, set the generator frequency to approximately 100 Hz . Adjust the output control for approximately 1- 3 V across the capacitor. Record the curren ...
Slide 2
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Slide 1

... Determine the current through the battery. Let E = 60 Volts, R2 = 20 W and R3=30 W. Simplify: R2 and R3 are in parallel ...
Slide 1
Slide 1

... • FM transmitters to transmit from digital music devices to car antenna • Between cities the unused radio frequency in one city might be used by a broadcasting station in the next • The synchronization of the transmitter and receiving radio frequencies can be quite time consuming • An automatic FM r ...
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Spark-gap transmitter



A spark-gap transmitter is a device that generates radio frequency electromagnetic waves using a spark gap.Spark gap transmitters were the first devices to demonstrate practical radio transmission, and were the standard technology for the first three decades of radio (1887–1916). Later, more efficient transmitters were developed based on rotary machines like the high-speed Alexanderson alternators and the static Poulsen Arc generators.Most operators, however, still preferred spark transmitters because of their uncomplicated design and because the carrier stopped when the telegraph key was released, which let the operator ""listen through"" for a reply. With other types of transmitter, the carrier could not be controlled so easily, and they required elaborate measures to modulate the carrier and to prevent transmitter leakage from de-sensitizing the receiver. After WWI, greatly improved transmitters based on vacuum tubes became available, which overcame these problems, and by the late 1920s the only spark transmitters still in regular operation were ""legacy"" installations on naval vessels. Even when vacuum tube based transmitters had been installed, many vessels retained their crude but reliable spark transmitters as an emergency backup. However, by 1940, the technology was no longer used for communication. Use of the spark-gap transmitter led to many radio operators being nicknamed ""Sparks"" long after they ceased using spark transmitters. Even today, the German verb funken, literally, ""to spark,"" also means ""to send a radio message or signal.""
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