Tektronix 516 series, Инструкция по эксплуатации

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Operating Instructions — Type 516
Input connector Input connector for signal through A VERTI­
CAL Channel.
B VERTICAL
(All controls in the B VERTICAL Channel are the same as
those in the A VERTICAL Channel except that they control
the signal applied through the B VERTICAL Channel input
connector.)
OTHERS
FOCUS
INTENSITY
ASTIGMATISM
POWER AND
SCALE ILLUM.
MODE
HORIZONTAL
POSITION
+GATE OUT
connector
SAWTOOTH
OUT connector
AMPLITUDE
CALIBRATOR*
CAL. OUT
connector
Focuses the trace or spot on the screen.
Controls the brightness of the trace or
spot on the screen.
Controls the roundness of the spot on the
screen.
Turns the instrument on and off, and con­
trols graticule illumination.
Provides for display of signal in A VERTI­
CAL Channel or B VERTICAL Channel in­
dependently, or both channels either on
alternate sweeps of the trace or alternate­
ly at 150-kHz rate.
Controls horizontal positioning of both A
and B VERTICAL Channel signals on the
crt screen.
Provides +25-volt (approximate) positive
gate coincident with sweep time.
Provides + 150-volt (approximate) sawtooth
waveform coincident with sweep time.
Selects amplitude of square-wave available
at CAL. OUT connector from 11 calibrated
steps.
Coaxial connector for supplying Amplitude
Calibrator output.
* On some instruments, this control is labeled SQUARE-WAVE
CALIBRATOR.
INITIAL OPERATION
The following paragraphs describe a simple procedure by
which you can become acquainted, in a general way, with
the controls of the Type 516 Oscilloscope and the effect
they have on its operation.
Initial Setup
To initially set up the Type 516 Oscilloscope for operation,
proceed as follows:
1. Connect jumper wires from the CAL. OUT connector to
the A and B VERTICAL Channel input connectors and set the
oscilloscope controls as shown in Fig. 3-1.
2. Adjust the FOCUS, INTENSITY, and ASTIGMATISM con­
trols to obtain
sharply
defined
traces o f useful
brightness.
3. Center one waveform in the upper half of the graticule
with the A VERTICAL Channel POSITION control and the
other waveform in the lower half of the graticule with the
B VERTICAL Channel POSITION control.
Functions of Controls
With the oscilloscope set up as described, turn the MODE
switch through each of its positions. Note that in the A
ONLY and B ONLY positions only one waveform is display­
ed, and in the ALTERNATE and CHOPPED positions, both
waveforms are displayed. (When the MODE switch is in the
CHOPPED position, the display may not be stable.) The dif­
ference between the ALTERNATE and CHOPPED positions is
described later in this section of the manual. Set the MODE
switch to the A ONLY position.
Set the red TRIGGER SELECTOR control to AC. Move the
TRIGGERING LEVEL control throughout its range, noting that
the waveform appears when the control is set toward the
middle of its range and disappears as it is set toward either
end of its range. Set the AMPLITUDE CALIBRATOR control
to 5. Move the TRIGGERING LEVEL control throughout its
range again, noting that the waveform is present during a
narrower portion of its range than before. Set the AMPLI­
TUDE CALIBRATOR control to 2. Note that the waveform
appears during still less of the range of the TRIGGERING
LEVEL control.
Set the AMPLITUDE CALIBRATOR control to 10 and the A
VERTICAL VOLTS/DIV. control to 10, and then to 20, ad­
justing the TRIGGERING LEVEL control as described in the
previous paragraph at each step. Note that the adjustment
of the TRIGGERING LEVEL control becomes more critical as
the triggering signal is reduced, whether by actual reduction
of the signal or reduction of vertical sensitivity. (Changing
the vertical sensitivity affects the amplitude of the triggering
signal only when an internal triggering signal is used.)
Set the AMPLITUDE CALIBRATOR control to 2 and the A
VERTICAL VOLTS/DIV. control to 10. Set the STABILITY and
TRIGGERING LEVEL controls fully clockwise. Turn the STA­
BILITY control counterclockwise until the trace disappears.
Then set the TRIGGERING LEVEL control for a stable display.
This is the method to use if a stable display is not present
when the red TRIGGER SELECTOR control is in the AUTO,
position, or cannot be obtained by means of the TRIGGERING
LEVEL control alone with the STABILITY control set in the
PRESET position.
Set the AMPLITUDE CALIBRATOR control to 1 and the A
VERTICAL VOLTS/DIV. control to 2, then to 5, then to 10,
and then to 20. At each setting of the A VERTICAL VOLTS/
DIV. control, adjust the STABILITY and TRIGGERING LEVEL
controls, as described in the previous paragraph, for a stable
display. Note that as the vertical deflection on the screen
becomes less, stable triggering becomes more difficult to ob­
tain, until at the higher settings of the VOLTS/DIV. control,
it may be impossible to obtain. This is because the setting
of the VOLTS/DIV. control also affects the amplitude of the
internal triggering signal. Normally, vertical deflection of
at least one-fifth of a major graticule division is required for
proper triggering from an internal signal.
Remove the jumper wire from the B VERTICAL input con­
nector and connect it from the CAL. OUT connector to the
3-3