59
TK-480/481
LEVEL DIAGRAM (TK-480)
RX Section
VCO
IC14
*
C131
PLL
Q10
C136
Q17
C193
Q11
D5
C149
Q12
C152
Power
module
D7
C169
L30
ANT
2.5W
–11.7dBm
(Q10 open)
–7.8dBm
(Q17 open)
–1.9dBm
(D5 open)
+7.1dBm
(Q12 open)
+17.5dBm
(C152 open)
RF (815.50MHz)
EMC
MIC
12
LPF
ALC
COMP
SW
IDC
6
DAC
I5
O5
DAC
I2
O2
13
15
16
18
19
9
8
IC12
16.6mV
rms
17.2mV
rms
39.2mV
rms
331mV
rms
320mV
rms
310mV
rms
IC4
IC3 (1/2)
IC4
*
487mV
rms
179mV
rms
311mV
rms
154mV
rms
AF
5
43
41
DAC
*
IC12
C58
IC3
IC4
AF
AMP
IC300
SP
500mW
(BTL)
203mV
rms
287mV
rms
419mV
rms
135mV
rms
29mV
rms
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
–119.0dBm
–119.4dBm
–120.4dBm
–107.0dBm
–110.3dBm
–106.8dBm
–116.4dBm
–109.6dBm
(C55 open)
241mV
rms
265mV
rms
–79.2dBm
–80.2dBm
RF (860.50MHz)
IF1 (44.85MHz)
IF2
(455kHz)
AF
T
o
make measurements in the AF section,
connect the oscilloscope proves directly.
(ANT input : –47dBm, 1kHz FM, 3kHz 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 3kHz Dev at 1kHz MOD.
T
o
make measurements in the
AF section, connect the
oscilloscope proves directly.
In the RF section, use a 1000pF
coupling capacitor
.
TX Section
Summary of Contents for FM Transceiver TK-481
Page 49: ...TK 480 481 TK 480 481 57 BLOCK DIAGRAM ...
Page 54: ...63 TK 480 481 ...