Sharp QT-50Z - FM IF;RF Adjustment; VCO Frequency Adjustment

FM IF/RF ADJUSTMENT
FM mono
4OOHz. 30%. FM modulated
-
DIAL
‘OINTEF
;ElTlNG
High
frequency
I
I.
i I
i
‘ur until no i
turn the core of T2
counter-clockwise
before taking it out oi
this bobbin.
2.Adjust for best “IF”
Figure 6-l FM IF
1
IF
I I
10.7 MH
Y -%7-
curve.
T2 IAdjust for best”S’ curve.
ther improvement can be made.
Lowest
frequency
10.7 MHZ
Highest
Adjust for maximal output
Figure 6-2 FM “IF” CURVE
Figure 6-3 FM “S” CURVE
88 MHz
108 MHz
8 IRepeat steps 4. 5 and 6. 7 until no further Improvement can be made
;I
I O
1
=
GND
GNO
VCO FREQUENCY ADJUSTMENT
Figure 6-4 FM RF
SIGNAL GENERATOR
400 Hz, 30%. FM unmodulated
(mono signal)
DIAL
FREQUENCY POINTER
ADJUST-
MENT
REMARKS
SETrING
FM
IC3
SlGNAL GENERATOR
FREO"UENCY
COUNTER
52
(See c&e$-6)
Figure 6-5 FM STEREO
FM mono position
98 MHz at 54 dB
98 MHz
FM stereo position
(unmodulated)
VRl
Adjust for 19.00 kHz
+ 200 Hz.
Figure 6-6 FM DUMMY
t
TPl
Figure 6-7 ADJUSTMENT POINTS
-6-