For part (c)
, after you calculate the new frequency of oscillation due to the spurious
phase shift (as I explained in the lecture),
1. you calculate the impedance magnitude (Z
T
(j
ω
)) of the tuned circuit at that new
frequency, and multiply it with g
mQ
/n to calculate the initial loop gain A
e
, which will
be less than 3, since the Z
T
(j
ω
) will be less than 1 k
Ω
. (Or you can simply
calculate how much lower the new Z
T
(j
ω
) is compared to the R
L
(1 k
Ω
), and
calculate the new A
e
by noting the A
e
used to be 3 when the Z
T
(j
ω
) used to be 1
k
Ω
at the old oscillation frequency).
2. From the equation for A
e
(=
)
b
(
I
)
b
(
I
2
b
1
0
), calculate the new b, from which you now
know what are new
i
v
)
and
o
v
)
.
3. From the new
o
v
)
, calculate the new output power.
For part (d),
read the sections related to Harmonic Distortion in Oscillator_Texts.pdf.
The following is a recap:
As long as the total harmonic distortion is less than about 10%, the waveform distortion
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 '08
 staff
 Multiplication, Frequency, Impedance, Phase Shift, harmonic distortion

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