Errors in Course Notes, Lectures etc.
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Page 43 Course Notes
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Middle of page, there is the statement that the gain of an 
exclusive-or style phase detector with power supplies at +1 V 
and -1 V has gain of pi/2 while the answer should have been 2/pi. 
This was further confused by the attempt to prove that 2 = 1/2.

Assignment 2 Error: 
------------------
  Phase detector II should have gain of 0.4 V/rad
  Phase detector  I should have gain of 1.6 V/rad
    - These two were swapped in the assignment.

Description of PLL Synthesizer
-----------------------------
  In class, Tuesday Nov 14, 2000, it was implied in a diagram 
  that when the divider constant N is varied, the VCO output 
  frequency is constant, and the frequency at the output of the 
  divider (the input to the phase detector) is varying depending 
  on what you are dividing by. This is shown below. For example, 
  if the VCO were constant at 1.2 Mhz (top trace), dividing by 
  6 results in 200 kHz (second trace) and  dividing by 8 results 
  in 150 kHz (third trace).
  
      _   _   _   _   _   _   _   _   _   _   _   _   _   _   _   _
VCO _| |_| |_| |_| |_| |_| |_| |_| |_| |_| |_| |_| |_| |_| |_| |_| 
      ___________             ___________             ___________  
/6  _|           |___________|           |___________|           |_
      _______________                 _______________              
/8  _|               |_______________|               |_____________
  
  
  This is wrong. What actually happens is that since the reference 
  frequency is constant, independent of N, the output of the 
  divider is also constant (shown on first line below, e.g., 
  at 100 kHz). Since the VCO output frequency is N times the 
  reference frequency, it is not constant as shown on second 
  trace where 100 kHz is multiplied by 6 so VCO output is at 
  600 kHz and on the third trace below where 100 kHz is multiplied 
  by 8 to result in VCO output at 800 kHz.

        _______________________                         _____________
fr   __|                       |_______________________|             
        ___     ___     ___     ___     ___     ___     ___     ___  
frx6 __|   |___|   |___|   |___|   |___|   |___|   |___|   |___|   |_
        __    __    __    __    __    __    __    __    __    __    _
frx8 __|  |__|  |__|  |__|  |__|  |__|  |__|  |__|  |__|  |__|  |__|