Thông tin thiết kế mạch P9 doc

... shown in Figure P9. 1. where the mark-to-space ratio is 1. Derive an expression for the PAM waveform given that, for a square wave, f ðtÞ¼ 1 2 þ 2 p P 1 n¼1 1 n sin not: P9: 5Þ Figure P9. 1. 302 SIGNAL ... the positive direction by D 2 acting as an ordinary diode and D 1 acting as a Zener diode. Their roles are reversed when the output voltage goes negative. The resulting square wave output...

Ngày tải lên: 01/07/2014, 10:20

... 1978. PROBLEMS 3.1 An AM receiver is tuned to 1000 kHz but two other stations (the first operating at 1010 kHz and the second operating at 1200 kHz) are causing interference. The intermediate frequency of the ... some of the power present in the wave and hence it will be acting as a receiver antenna. However, other electromagnetic waves emanating from all other radio transmitters will also ind...

Ngày tải lên: 01/07/2014, 10:20

... amplitude of the modulating signal. In frequency modulation, the amplitude of the carrier is kept constant and its frequency is changed in accordance with the amplitude of the modulating signal. It ... found which will convert changes in frequency to changes in amplitude, the techniques used for detecting AM can be used for FM as well. In Section 4.3.3.4, three frequency-to-amplitude conversi...

Ngày tải lên: 01/07/2014, 10:20

... the electrons on arrival at the target, a second ring of graphite coating, called the decelerator grid, is provided. By adjusting the voltages on the accelerator anode and the decelerator grid, ... transmitter. 6.3 COMPONENT DESIGN 163 The negative value has no physical meaning and it is neglected. Substituting into Equation (6.3.19), we get q ¼ 0:414 ¼ L 4L crit ¼ L R 2 D C g ð6:3:23Þ and L...

Ngày tải lên: 01/07/2014, 10:20

... clear that, by depositing the different phosphors materials in dots grouped in threes at the appropriate points on the screen, the different colors can be reproduced by modulating the relative saturation ... operation, this circuit does not consume much power, neither is there a large reactive power circulating in the circuit. 7.2.7.5 Horizontal Deflection System. From Figure 7.3, it can be se...

Ngày tải lên: 01/07/2014, 10:20

... some property of a continuous sinusoidal high-frequency source in accordance with speech, then the prospects for effective communication through free space become a distinct possibility. Changing ... we restrict each transmitter to one specific frequency (that is, continuous sinusoidal waveforms) then interference can be avoided by incorporating a narrow-band filter at the receiver to eliminate...

Ngày tải lên: 01/07/2014, 10:20

... finger wheel is rotating in the clockwise direction, the lever X is free to move out of the way of the cam lobes without disturbing the switch lever Y. When the wheel assembly is rotating in the counter-clockwise ... oscillating frequency if the oscillator is designed to operate at the frequency of the null. However, using the classical twin-tee values of Rs and Csin oscillator design will be...

Ngày tải lên: 01/07/2014, 10:20

... from a fluorescent lamp onto the document. A spherical lens brings into focus a row of pixels formed from a line 0.005 inches (0.127 mm) wide (200 lines per inch). The document is moved one row at ... receive machine then sends back a code indicating that the message was successfully received. 12. The send machine goes back ‘‘ on-hook,’’ terminating the call. 13. The receive machine also goes...

Ngày tải lên: 01/07/2014, 10:20

... number of chips representing a message bit (1 or 0) is large, the correlation does not have to be perfect; it has to correctly recognize the majority of the chips as representing that message bit ... Film Bulk Acoustic Resonator (FBAR). Ceramic RF duplexers are considered to have superior operating characteristics compared to SAW devices but they are, in general, bulkier. FBAR is a new techno...

Ngày tải lên: 01/07/2014, 10:20

... of reliability. To avoid the complexity of tracking the satellite from rising to setting and to maintain continuous communication, it is best to ‘‘park’’ the satellite at a point directly above ... adaptively controlled to correct for changes in temperature and other operating conditions. Coaxial cable is used for transmitting data at 274.176 Mbit=s in the LD-4 (Bell- Canada) and T4M (Bell Sy...

Ngày tải lên: 01/07/2014, 10:20