Service manual

Guarding circuit:
The 11V of the line-stage is monitored.
The +28V winding (pin 6) of supply-transformer 5506 is monitored. (These pulses, when
switching off the set, exist longer than the 11V-level)
When switching off the set by the 'POWER'-switch, the 11V will decrease and will
generate a positive STAND-BY (POR) pulse.
At that moment the RGB-outputs will be driven such that the EHT-capacitor is heavily
loaded in order to have a nice switch off spot. Therefore, when the set is 'on', T7510 is
always conducting.
The switch off spot is nicer then without extra sensing of +28 V winding.
The STAND-BY (POR) signal drives via R3545 a positive pulse back to the Painter-
processor. The Painter will switch off the Main Supply via the HOP IC. It will put the
HOP in HOP-standby, stopping the drive pulses. The main supply will be switched off.
(See diagram B4)
SSB
There are three voltages used for the SSB: +8 V, +5.2 V and +5 V.
+5.2 V is the Standby voltage; it should always be present. The 8V is derived from the
11D V with stabilizer 7906 (on LSP). This 11D voltage is only present when the line-
drive pulses start the deflection.
The 8V is used to switch the +5.2 V with transistor 7905 to supply the +5 V.