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2.
I
RCU IT DESC R
C
2.1.
BLOCK DIAGRAM DESCRIPTION (see Fig.
2 . 1 . I .
Vertical Deflection
The vertical deflection system is located on the PRE-AMPLIFIER
U N I T 8 AND FINAL AMPLIFIER UNlT9.
The instrument has two identical vertical channels, A and B: only channel A i s described.
Channel A vertical input signal i s fed via the SIGNAL COUPLING switch AC-0-DC (S17) to the HIGH
IMPEDANCE ATTENUATOR, which i s controlled via reed relays by the AMPL/DIV switch.
Attenuation factors of XI,
The IMPEDANCE CONVERTER adapts the output of the HIGH IMPEDANCE ATTENUATOR to the input
the LOW IMPEDANCE ATTENUATOR, which is also controlled
give attenuatons of x 1, x2 and x5.
For the three most sensitive ranges (2-5-10 mV/div), the signal i s amplified by a factor of 10. This is achieved
in the AMPLIFIER circuit controlled by the AMPL/DIV switch.
Via the CONTINUOUS AMPL/DIV, controlled by the AMPL/DIV continuous control, the signal is fed to the
AMPLIFIER circuit. The AMPLIFIER
From the TRIG. PICK-OFF of the AMPLIFIER, the channel A trigger signal i s routed to both time-bases.
Returning to the display signal path, the output signal of the AMPLIFIER is fed to an integrated circuit
comprising the vertical POSITION, the NORMAL/INVERT circuit and the VERTICAL CHANNEL SWITCH circuit.
The vertical POSITION control circuit allows vertical shift of the c.r.t. trace. Incorporated in the POSITION
control, the PULL TO INVERT switch controls the NORMAL/INVERT circuit.
The VERTICAL CHANNEL SWITCH is controlled by the vertical display mode switches A, ALT, TRIG VIEW,
CHOP, ADD, B, via the VERTICAL CHANNEL SELECTION LOGIC circuit. In A L T mode, the A and B
channel switching i s controlled by the A L T pulse derived from the HORIZONTAL CHANNEL SELECTION
LOGIC.
In the CHOP mode, the switching period between channels A and B is blanked by the Z amplifier (via the
Z-logic) controlled by the CHOPPER BLANKING signal derived from the VERTICAL CHANNEL SELECTION
LOGIC.
The TRIG VIEW signal, derived from the MTB trigger INTERFACE, can also be selected by the vertical display
mode switches to enable display of the MTB trigger signal.
When the pushbutton ADD i s depressed, the input signals of both vertical channels are added.
From the VERTICAL CHANNEL SWITCH, the selected vertical signal i s fed via the DELAY LINE DRIVER to
the DELAY LINE.
In the DELAY LINE DRIVER the current signal is converted to
are also suppressed in this
The COMP. TRIG. signal is routed to the TRIGGER INPUT STAGE of the time-base for composite triggering.
From the DELAY LINE DRIVER, the adapted output signal is fed to the DELAY LINE, which gives sufficient
delay to ensure that the steep leading edges of fast signals are displayed.
To reduce and t o compensate for interference and distortion originating in the DELAY LINE, the signal is fed
t o the DELAY LINE COMPENSATION CIRCUIT before being applied to the FINAL VERTICAL AMPLIFIER.
The vertical distance on the screen between the traces of the two time-bases in the ALT TB mode, is controlled
by the trace separation signal applied to the FINAL VERTICAL AMPLIFIER.
The output signal of the FINAL VERTICAL AMPLIFIER feeds the vertical deflection plates of the c.r.t.
- -
Horizontal Deflection
The triggering circuits
Both the main time-base and the delayed time-base are located on the TIME-BASE UNIT 2.
The FINAL HORIZONTAL AMPLIFIER and the Z-AMPLIFIER are situated on the FINAL AMPLIFIER
UNIT 5.
I
PT ION
2 . 1 . )
achieved in this portion of the attenuator circuit.
converts the voltage signal into
stage
stage.
both the MTB and the DTB
for
+
TRIGGER UNIT 3, DELAY LINE
reed relays by the AMPL/DIV switch to
via
current signal.
a
a
voltage signal and the common-mode signals
located on the PRE-AMPLIFIER -TRIGGER UNIT 3.
are
2-3
of
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