FORMeSWRTHYPHASCISPELPRGHDOC h PICP69LINP6Z BOXP6Z dOVLP6Z dSWCL@BlackWhiteRedGreenBlueCyanYellowMagentafSalmonwPeachUBrownellowLight GreenwwwGrey DarkOrangeݙVanillalowGrey LightIDXHIDXDSoftSansdTitleepz,IDXDSoftSansdBlank LinefIDXDSoftSansdLetter HeadergIDXDSoftSans dIndex EntryhTOCH TOCDSoftSansdTitlenz%TOCDSoftSans dBlank LineoTOCDSoftSansdZLevel 1pTOCDSoftSans dZLevel 2qTOCDSoftSerif dLevel 3rTOCDSoftSerif dhLevel 4sTOCDSoftSerif dvLevel 5tTOCDSoftSerif d*Level 6uTOCDSoftSerif dLevel 7vTOCDSoftSerif d8Level 8wIDXPSEC1 PTPAG3pA PRN3KBVtils:APPLICATIONS/FinalWriter/FWFonts/SWOLFonts/Serif/WŬWW~WW { dELX.FormulaText{WPASDSoftSansdDocument TitlePASDSoftSansdSection Namepz??PASDSoftSansdTopic Nameq{??PASDSoftSansdSub Topic 1r|??PASDSoftSansdSub Topic 2s}??PASDSoftSans dBodyPASDSoftSans dIndented BodyTOCP!rOUTPBIBPTOIPENDPDSP2PHHFDASoftSans dSoftSans dPNDASoftSans dSHPP6Z dGRMRStrictly.For Business Writing.For Casual Writing.Custom 1.Custom 2.Custom 3.IDXLConductorsTDINFFCOP3`W8.W0%FDTASoftSans_Bold{WŬWΆWvtUtils:APPLICATIONS/FinalWriter/FWFonts/SWOLFonts/LW0:PTMainTBDYRULENATTR dCHRSElectronic Servicing yr.1 pt.1ATTR dCHRS ATTR hdCHRS ATTR hdCHRS ATTR dCHRSLecture: 030 - tATTR [dCHRS ATTR hdCHRS ATTR hdCHRS ATTR hdCHRS ATTR hdCHRS Thurs. - 22ATTR hdCHRS - May ATTR hdCHRS- 1997RULEATTR hdCHRSRULEATTR xCHRSOther Electronic CircuitsRULE ATTRdCHRSRULE ATTRdCHRSSpeed Control SystemRULEATTR dCHRSRULE.ATTR. dCHRS.The set speed control (Block A), which is regulated by the user for a selected speed (eg 500 revs per minute). This signal enters the differential amplifier (Block B) and finally it is assumed that the D.C. motor (Block D) rotates at the speed (500 r.p.m.). While the d.c. motor is rotating the load, it also drives a d.c. generator (Block E) whose output is on indication of how much the motor speed is rotating. If the load increases a +Ve voltage output is produced at the output of the dc generator, which goes into the Differential amplifier (block B). RULEATTR dCHRSRULEATTR dCHRSIf the two inputs (from the speed control and DC generator) are the same, no voltage is produced, amplified, and fed to the motor. But, if there is a difference, due there is an error between the speed control, and the actual speed the motor+load is rotating, the difference in voltage between these two inputs is given from the differential amplifier, which is then amplified by the power amplifier (Block C), and causes the motor to increase in speed until it matches the required speed. Once this happens, the two inputs entering the differential amplifier will now be equal, and the motor acceleration is stopped, as no output voltage is produced from block B and C.RULEATTR dCHRSRULEATTR dCHRSRULE ATTRdCHRSPhase Locked LoopRULEEBATTR dCHRSThe ATTR dCHRSphaselocked loopATTR1 dCHRS1 serves to synchronize an oscillator with an external signal so that the frequency and phase is the same as that of the external signal source. This is used in clock oscillators in computers and the synchronization of a reference oscillator in a colour TV received decoder with a transmitted colour burst.RULEATTR dCHRSRULEBATTRB dCHRSBThe oscillator to be synchronized is that coming out from the Voltage controlled Oscillator (Block D), which has a sine waveform of constant frequency. This oscillator is designed so that when DC voltage is fed in it, the phase of the frequency given is altered depending the magnitude of the dc voltage. The v.c.o. output is passed from the buffer Amplifier (Block E) to reduce the effects of variable loading but the rest of the circuit on the v.c.o. The output from E (fo) is fed in the Phase discriminator (Block A) which has another input, being the reference signal (fs). RULEATTR dCHRSRULEATTR dCHRSThe Phase discriminator detects changes in phase between the two input signals (fo and fs), and sends a dc voltage output depending the how large is the difference. If the two signals are in phase and of same frequency, 0V is sent by the phase oscillator, and maximum voltage when the two signals are 180 out of phase, or different frequency. This DC voltage produced is referred as the DC error signal.RULEATTR dCHRSRULEATTR dCHRSThis signal is passed from Low Pass Filter (B) and amplified by a DC amplifier (C) and fed into the Voltage Controlled Oscillator. The filter assures that only DC is passed, and the DC amplifier makes the voltage to a suitable level to control the v.c.o. Since the DC error voltage depends on the difference between fs and fo, it makes the v.c.o. to change the phase so that automatically becomes the same as the reference signal. RULEATTR dCHRSRULEATTR dCHRSOnce the v.c.o. has acquired frequency and phase locking with the reference signal input, any tendency for the v.c.o. to change either its frequency or phase due variations in temperature or supply voltage, will be counteracted by the phase locked loop.RULEATTR dCHRSRULEATTR dCHRS RMSTRULEATTR dCHRSLMSTRULEATTR dCHRS