Iiyama Vision Master Pro 451, Service Manual

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1-2. ANODE VOLTAGE adjustment [PWB-MAIN]
1)
2)
3)
Receive a cross-hatch inverted signal of MODE 1 when applying the AC
voltage of 110±10V.
Connect the DC voltmeter between CONNECTOR TP and GND (chassis).
Adjust the voltage to DC 80±0.5V with VR951 (80V-ADJ).
1-1. 80V-ADJ adjustment [PWB-MAIN]
1)
2)
3)
4)
5)
6)
7)
Receive a cross-hatch inverted signal of MODE 5.
Turn OFF the Power Switch.
Connect a high-voltage probe between CRT anode and GND (chassis).
Turn ON the Power Switch.
Adjust the high-voltage to 26.0±0.2kV with VR501 (HV-ADJ).
Confirm the variation of high-voltage is within ±0.2kV when receiving MODE
1 and MODE 6 respectively.
Turn OFF the Power Switch and remove the high-voltage probe.
WARNING !
VR501 (HV-ADJ) has been carefully factory-adjusted for each unit in order
to satisfy regulations regarding X-radiation.
Further adjustment on VR501 shall not be performed.
In case of adjustment, the adjusted position of VR501 must be fixed by a
soldering iron to prevent it from rotating.
Voltage
VR951 80V-ADJ
Voltage
VR501 HV-ADJ
1-3. POWER FACTOR CIRCUIT confirmation [PWB-MAIN]
1)
2)
3)
4)
5)
6)
Receive a cross-hatch inverted signal of MODE 5.
Turn OFF the Power Switch.
Connect the DC voltmeter between TP4 and TP0.
Turn ON the Power Switch.
Confirm that the voltage is DC 400±10V.
Remove the DC voltmeter.