Furuno CH-270, Service Manual

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22
3.3 Adjustment
Use the proper instrument, otherwise the unit malfunctions.
DISP Board (06P0238)
Adjusters Measuring Points Measured by Rating Remarks
R65 TP12 Frequency
Counter
70 kHz ±1 kHz Switching frequency of
power circuit
R75 TP7 Digital
Multimeter
12.1 V9 ±0.1 V
C63 TP4 Digital
Multimeter
2.40 V ±0.05 V LCD Clock Phase
Adjustment
CPU Board (06P0258)
(1) R. G. B Level Adjustment
Adjusters Measuring Points Measured by Rating Remarks
R86(R) TP15
R87(G) TP16
R88(B) TP17
Oscilloscope 1.0 Vpp ±0.05 V Set screen color to white
With test-pattern selection
in system menu screen.
(2) ROLL, PITCH Adjustment
Adjusters Measuring Points Measured by Rating
R101 TP13 Digital
Multimeter
3.5 V when the pitch angle is zero.
R102 TP14 Digital
Multimeter
3.5 V when the roll angle is zero.
PWR Board (06P0242)
Adjusters Measuring Points Measured by Rating Remarks
R34 J2 #1 Digital
Multimeter
5.0 V ±0.01 V
R29 TP5--TP6(GND) Frequency
Counter
68.0 ±0.05 kHz Switching frequency of
VTX voltage regulator
R13 J8 #1 Digital
Multimeter
77 V VTX voltage
TRX Board (06P0241)
The receiver in TRX board is adjusted by following steps below.
Instruments
1) Signal Generator
2) Volt-meter (dBuV)
3) Matching Transformer : 02S1138-1
4) Digital multi-meter
Connection
Connect the SG to J6 #1 and #2 on the TRX board via the Matching Transformer
02S1138-1, as shown in the Fig. 3.4.