Philips PM3219/01 Notice D'emploi page 25

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1.5.7.
1.5.8.
Z Amplifier ;
The Z AMPLIFIER is controlled by timing signals derived from the horizontal time-base channels to provide
trace blanking of the c.r.t. during the flyback and hold-off time.
In addition, controlled by the vertical logic, it blanks the sweep during switching transients in CHOP mode.
Trace blanking from an external source is possible via the rear-panel socket Z-MOD IN.
The |.f. components of the blanking signal are modulated and demodulated (for voltage isolation purposes)
before they are applied together with the a.c.-coupled h.f. voltage components to the Wehnelt cylinder.
Power supply
The power supply operates either from a.c. mains voltages of nominally 110 V, 220 V or 240 V, or optional
from a d.c. source of 21 - 30 V.
A switched-mode circuit employing an integrated circuit provides smoothed d.c. outputs of +180 V, —180 V,
+38 V, +5 V, +12 V, -12 V, +60 V, —60 V.
The EHT voltage for the accelerator anode of the c.r.t. is derived from a voltage quadrupler circuit taken from
the converter transformer secondary circuit that supplies the —1500 V for the cathode of the c.r.t.
The CAL unit provides the calibration square-wave voltage.