Tektronix 570, Руководство пользователя

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Non-Regulated Supplies
V505 and V506 supply + 400 volts and -300
volts with respect to the common lead. This
s upply is sometimes grounded directly and at
other times connected to the current-measuring
resistors as shown on the CRT -Display Switch­
ing Diagram. C502 balances the stray capacitive
c u rrent to ground so that this current does not
flow through the current measuring resistors.
+ DC Circuit
The + DC Circuit receives + 400 volts and -300
volts , unregulated, from either the Main Power
Supply or the Floating Power Supply. This is
determined by the setting of the PLATE-GRID
s witch shown in the CRT -Display Switching
D i agram. The output of the + DC circuit is
v ariable from approxi 10 volts to + 300
volts.
Screen voltage for the Series Regulator Tube,
V 5 1 5 , is obtained from the full-wave rectifie r ,
V 5 1 O . C 5 1 0 A and C510B with R 5 1 0 reduce the
ac ripple on the screen. The negative side of
the supply is tied to the cathode of V 5 l 5 so
that the screen to cathode voltage rel!lains the
s arne as the output voltage is changed. C509
b alances the capacitive current to ground in the
ci rcuit which supplies screen voltage for V 5 1 5 .
Reference voltage for V525B i s obtained from
the + DC VARIABLE Control which is connected
b etween
-
1 5
0
volt supply and +
lO�Y.
V540B
iso lates the reference voltage supply from the
S e ries Regulator so that no current will flow
b etween the two circuits. V525A and V525B are
C omparator Tubes. The voltage at a tap on the
divider between the output of the Series Regulator
and the reference voltage are compared with
ground potential. The amplified error signal at
t h e plate of V525B is applied to the grid of the
S eries Regulator Tub e , V 5 1 5 . B 5 1 5 and B 5 1 6
r educes the dc level of signal at this grid without
attenuation of the signal.
The + DC switch changes the divider ratio
in the divider at the grid of the comparator
tube , V525B. The + DC V A RIABLE Control
c h anges the reference voltage at the bottom
o f this divider through V540B. These two
controls provide continuous variation of the
o u tput of the regulator from approximately
+ 10 volts to + 300 volts.
CRT C I R C U I T DIAGRAM
Accelerating voltage for the cathode -ray tube
is obtained by rectifying a 60 -kc voltage produced
b y a vacuum tube oscillator. V610 is the
osci llator tube with the primary of T620 serving
as a tapped inductor. Rectifiers V630 and V63 1
s upply - 1700 volts to the crt cathode and + 2300
volts to the post acceleration anode for a total
of 4 kv accelerating Voltage.
The high voltage is adjusted by means of
R626 in the regulator circuit. The voltage at
this point is compared with - 1 50 volts in
V605A. The amplified error signal is applied
to the grid of the Shunt Regulator Tube, V605B ,
which varies the screen voltage of the oscillator
tube.
The INTENSITY, FOCUS, and ASTIGMATISM
C ontrols adjust the cn operating voltages for the
desired intensity and focus the beam.
The
G EO M
ADJ
Control adjusts the voltage on the
s econd anode of the crt for best linearity at the
extremes of deflection.
3 - 6
C ircuit Des cription -Type 570
AA