Cantirrnation Of Operation And Readjustment; Outline; Adjustment Of 2 Pa Units; Adjustment Of Heat Sensor - JRC JRL-2000F Service Manual

4. Confirmation of Operation and Readjustment
4.1 Outline
When an FET is replaced in the PA unit, "4.2.2 Adjustmemt of ldling
Current'~
is re-
quired. . . . . . .
When the PA unit is replaced, "4.4.2 Adfustment of APC Circuit" and "4.4.3 Adjustment
of ALC Circuit" is required.
When the power supply unit is replaced, "4.3.1 Adjustment of Output Voltage" and
"4.4.1 Adjustment of Meters" is required.
4.2 Adjustment of 2 PA Units
. All adjustable parts of the PA unit are in the CCB-367 PA control circuits.
4.2.1 Adjustment of Heat Sensor
[ Required instruments ]
(1 )Digital tester
(2) Thermometer
< Adjustment procedures >
(1 )Measure TP1 valtage with a digital tester.
TP1 voltage: ETP1 140Q-1500mV
(2)Measure the room temperature (Ta).
(3)Calculate TP3 valtage to be adjusted with the following formula:
ETP3=ETP1-(75°C-Ta) X 4.5
[Example] Where ETP1=1450 mV and Ta=25°C,
ETP3=1450-(75-25) X 4.5 = 1450-220=1230 mV
(4)Adjust RV1 to the calculated valtage while measuring TP3.
(5)0btain ETP2 by measuring TP2 voltage.
Using the same formula in step (2),(3)
ETP4=ETP2-(75°C-Ta)X 4.5
Adjust RV2 to the calculated valtage while measuring TP4.
(6)Confirm that the fan does not oparate in this state.
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