Measurements And Adjustment - Furuno FS-1503 Service Manual

5.6 Measurements and Adjustment

CAUTION: Do not turn any adjusters until you understand their functions. The
measuring instruments must be calibrated before using.
Electrical Shock Hazard:
This equipment contains high voltages which can cause death at several
internal circuits. Any internal adjustment, servicing and repair shall only be
perfomed by qualified service personnel totally familiar with electrical circuits
and servicing of the equipment. A residual charge remains in capacitors and
other devices several minutes after turning off the power.
It is therefore essential to wait at least 3 minutes to allow residual charge to
subside before acceessing the inside of the equipment.
1. Adjustment
Board Item
Overvoltage
protector
PA
temperature
PA/FIL
DRIVE
(050667) TR (Q4/Q5)
BIAS
PA TR
(Q6/Q7)
BIAS
CPU Contrast
(05P0665) Adj.
Output
power Adj.
SW REG
(05P0668) Oscillation
Freq Adj.
Phase Det.
COUP
Balance
(05P0669)
Adj.
DANGER
Table 5-2 Adjustment (1/2)
Setting Adjuster
Input voltage: 17.0 to
18.5 V
Temperature: 25 °C
Disconnect
[EXC IN], PTT ON
Disconnect
[EXC IN], PTT ON
-
Input voltage: 13.6 V
Input voltage: 13.6 V
-
5-12
Check Point
- -
J1 #7 (H) and
-
9 (C)
- R69
R39 FL3
TP1 (H) and
R1
TP2 (C)
J2 #1 (H) and
R15
3 (C)
TP1 (H) and
-
TP2 (C)
R24 -
Level Remarks
Power: off
1.0 ± 0.1 V
40 to 60 mV
500 mA ±
50 mA
Use high Z
3.3 ± 0.05 V
voltmeter.
13.0 V
170 kHz ±
Optional
20 kHz
(22 Vpp)
May be changed
Mid. point
to fixed resistor