Level Diagram - Kenwood NX-740H Service Manual

LEVEL DIAGRAM

Receiver Section
RF (Center Frequency)
5
N: -120.5dBm
N: - 118dBm
ANT
LNA
BPF
Q506
G1
4
To make measurements in the RF section, connect the RF level meter.
In the RF section, use a 0.01uF coupling capacitor.
(The display shows the SSG input value required to obtain 12dB SINAD.)
Transmitter Section
AF (1KHz)
3
2.40mVrms
4.19mVrms
50.1mVrms
MIC
Baseband IC
IC 706
MIC amplifier
IC709
2 20 20
1 21
To make measurements in the AF section, connect the AC level meter.
AG is set so that MIC input becomes 1.5kHz (Narrow) DEV at AF :1kHz .
2
1
A B
IF_1 (49.95MHz)
N: -114dBm
N: - 98.5dBm
N: -96.5dBm
IF amplifier
MCF
Mixer
BPF
Q503 XF500
D
D G1
TX VCO
76.4mVrms
5.4dBm
-12dBm
Baseband IC
Q7
Q11
IC709
24
C
(No.RA010<Rev.001>) 2-8
IF_2 (450kHz)
71mVrms
N: -97dBm
FMIC
IC500
Q501 IC501
9
16
To make measurement in the AF section, connect the AC level meter.
(ANT input: -53dBm, AF 1kHz FM,Dev 1.5kHz
The AF output level is adjusted near 4.0Vrms / 4ohm by adjust VOL key.
RF (CENTER FREQUENCY)
TX-RX unit
3dBm
6.2dBm
23dBm
DRIVE FET
Q12
Q300
C301
C108 D16
C101
To make measurements in the RF section, connect the RF Wattmeter (50ohm).
In the RF section, use a 1000pF coupling capacitor.
D E
2-8 (No.RA010<Rev.001>)
AF Frequency (1kHz)
228mVrms
73mVrms
72mVrms
0.091Vrms
246mVrms
Baseband IC
Baseband IC
IC715
IC709 IC709
16 17 16
26 13 15
Power Module
TX-RX unit
17dBm
FINAL FET
ANT
IC300
1 4
D305
C313
D306
F
4 Vrms
4.51 Vrms
IC719 J701
10
1
H : 50W
M : 25W
L : 5W
50
G