60
TK-480/481
LEVEL DIAGRAM (TK-481)VCO
IC14
*C131
PLL
Q10
C136
Q17
C193
Q11
D5 C149
Q12
C152
Power
module
D7 C169
L30 ANT
2.5W
–10.2dBm
(Q10 open)
–7.4dBm
(Q17 open)
–0.4dBm
(D5 open)
+5.3dBm
(Q12 open)
+17.8dBm
(C152 open)
RF (899.00MHz)
EMC
MIC 12 LPF ALC COMP
SW
IDC 6DAC
I5 O5 DAC
I2 O2
13 15 16 18 19 98
IC12
16.1mVrms
16.7mVrms 41.2mVrms 353mVrms 338mVrms 318mVrms
IC4 IC3 (1/2) IC4
*
530mVrms 133mVrms 109mVrms 54mVrms
AF
5
43
41 DAC
*
IC12
C58 IC3 IC4
AF
AMP
IC300 SP
500mW
(BTL)
188mVrms 254mVrms 376mVrms 132mVrms 29mVrms
AF
C169
L30
ANT
C143
L11
C139 Q9 C122
L20
C110 Q6 R60
XF1
R51
Q5 C55
FM IF
SYSTEM
CF1,2 IC8
AMP
*
–118.0dBm –118.4dBm –118.4dBm –118.0dBm –108.3dBm –106.6dBm –105.5dBm –117.0dBm –107.5dBm
(C55 open)
115mVrms 268mVrms
–58dBm –55dBm
RF (938.00MHz) IF1 (44.85MHz)
IF2
(455kHz) AF
To make measurements in the AF section,
connect the oscilloscope proves directly.
(ANT input : –47dBm, 1kHz FM, 1.5kHz dev.)
In the RF section, use a 1000pF coupling capacitor.
(The display shows the SSG input value required
to obtain 12dB SINAD.)
AG is set to the MIC input
becomes 1.5kHz Dev at 1kHz MOD.
To make measurements in the
AF section, connect the
oscilloscope proves directly.
In the RF section, use a 1000pF
coupling capacitor.