The video circuit illustrated in Figure 1 combines an audio-subcarrier notch filter and group-delay equalization as required by the ITU-470 standard. It also includes an amplitude-adjustment capability for driving an RF video modulator in NTSC applications. (PAL operation requires a minor adjustment of the filter and all-pass values. ) For best per
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formance, the input should be driven from a low-impedance source, such as an op amp or active filter. Two second-order all-pass stages (U1a, R1, C1, L1 and U1c, R13, C3, L3) and a first-order all-pass stage (U1d, C4, R14) form a fifth-order group-delay equalizer that compensates for group delay introduced by the notch filter (U1b, R6, C2, L2). Potentiometer R7 adjusts the output amplitude as required by the modulator in use. The notch frequency is set by L2 and C2, and the notch depth and bandwidth are set by R4, R5, and R6. Typical notch depth is greater than 16 dB ( Fig. 2 ). Flatness above 2. 5 MHz is ±0. 5 dB.
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
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The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
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This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
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