![Tektronix 422 Instruction Manual Download Page 25](http://html1.mh-extra.com/html/tektronix/422/422_instruction-manual_1078891025.webp)
Operating Instructions—Type 422 AC-DC
Fig. 2-10. Removing the light filter or faceplate protector.
The tinted light filte r minimizes light reflections from
the face of the CRT to improve contrast when viewing the
display under high ambient light conditions. A clear plastic
faceplate protector is also provided fo r use when neither
the mesh nor the tinted filte r is used. The clear faceplate
protector provides the best display fo r waveform photo
graphs. It is also preferable fo r viewing high writing rate
displays.
A filte r or faceplate protector should be used at all times
to protect the CRT faceplate from scratches. The faceplate
protector and the tinted light filte r mount in the same hol
der. To remove the light filte r or faceplate protector from
the holder, press it out to the rear. Both can be replaced by
snapping them back into the holder.
Vertical Channel Selection
Either o f the input channels can be used fo r single-trace
displays. A pply the signal to the desired INPUT connector
and set the vertical Mode switch to display the channel
used. Since channel 1 only triggering is provided only in
Channel 1, and the invert and X10 AC gain features are
provided only fo r Channel 2, the correct channel must be
selected to take advantage of these features. For dual-trace
displays, connect the signals to both INPUT connectors and
set the vertical Mode switch to one of the dual-trace
positions.
Vertical Gain Adjustment
To check the gain o f either channel, set the VO LTS/DIV
switch to the CALIBRATE 4 DIVISIONS position and the
V A R IA B LE control to CAL. The vertical deflection should
be exactly four divisions. If not, adjust the front-panel
GAIN adjustment fo r exactly fo ur divisions o f deflection.
NOTE
If the gain o f the two channels must be closely
matched (such as fo r ALG ADD operation), use the
adjustment procedure given in the Calibration Proce
dure
The best measurement accuracy when using probes is
provided if the GAIN adjustment is made w ith the probes
installed. This compensates fo r any inaccuracies o f the
probes. Set the VO LTS/DIV switch to .05 and apply an
accurate square wave to the probe tips. Also, to provide the
best measurement accuracy, calibrate the vertical gain of
the Type 422 at the temperature at which the measurement
is to be made.
Step
Attenuator
Balance
Adjustment
To check the step attenuator balance of either channel,
set the Input Coupling switch to GND and the TRIG G ER
ING modeswitch to AUTO. Change the VO LTS/DI V switch
from .05 to .01. If the trace moves vertically, adjust the
front-panel STEP A T T BAL adjustment as follows:
1. With the Input Coupling switch set to GND and the
VO LTS/DI V switch set to .05, move the trace to the center
horizontal line of the graticule w ith the vertical POSITION
control.
2. Set the VO LTS/D IV switch to .01 and adjust the
STEP A T T BAL adjustment to return the trace to the
center horizontal line.
3. Repeat steps 1 and 2 fo r minimum trace sh ift as the
V O LTS /D IV switch is changed from .05 to .01.
Signal Connections
In general, probes offer the most convenient means o f
connecting a signal to the input o f the Type 422. Tektronix
probes are shielded to prevent pickup of electrostatic inter
ference. A 10X attenuator probe offers a high input imped
ance and allows the cirucit under test to perform very close
to normal operating conditions. However, a 10X probe also
attenuates the input signal 10 times. A T ektronix field ef
fect transistor probe offers the same high-input impedance
as the 10X probes. However, it is particularly useful since it
provides wide-band operation while presenting no attenua
tion ( IX gain) and a low input capacitance. A standard I X
probe can be used fo r signal connection, although it does
not provide as high an input impedance and may result in a
lower overall bandwidth. Specialized probes are also avail
able from Tektronix, Inc. fo r high-voltage measurement,
current measurement, etc. See the Tektronix, Inc. catalog
fo r characteristics and compatability of probes fo r use w ith
this system.
In high-frequency applications requiring maximum over
all bandwidth, use coaxial cables terminated in their charac
teristic impedances at the Type 422 INPUT connectors.
High-level, low-frequency signals can be connected directly
to the Type 422 INPUT connectors using short unshielded
E
2-15
Summary of Contents for 422
Page 4: ...R TV 422 AC OC P o p p Type 422 AC DC ...
Page 64: ...Circuit Description Type 422 AC DC 3 26 Fig 3 15 Idealized DC DC Regulator circuit waveforms ...
Page 68: ...NOTES ...
Page 90: ...Maintenance Type 422 AC DC 4 22 Si Fig 4 14 High Voltage Rectifier Multiplier circuit board ...
Page 92: ...Maintenance Type 422 AC DC 4 24 Fig 4 16 DC Power Converter circuit board ...
Page 93: ...Maintenance Type 422 AC DC E 4 25 Fig 4 17 DC Power Control circuit board ...
Page 94: ...NOTES ...
Page 132: ...NOTES ...
Page 158: ......
Page 180: ...B U D C K D A G A N s N e o o o o u p T Y P E 4 Z 2 A C D C 0 2 foe ...
Page 187: ...T Y P E 4 1 2 A C D C l S W E E P T R I G G E R 3 s M 2 0 0 0 0 U P 1268 SWEEP TRIGGER ...
Page 191: ... H O R I Z O N T A L A M P L I F s N z o o o o u p H O R I Z O N T A L AMPLIFIER ...
Page 192: ... ...
Page 195: ...CRT CIRCUIT 10 3 f 8 OS M hS q u a gs u 0 z 3 U js o 0 1 j C V J C J u l Q ...
Page 198: ...FIG 1 FRONT TYPE 422 AC DC ...
Page 199: ...FIG 2 CHASSIS ...
Page 200: ...4 I TYPE 422 AC DC FIG 2 ...
Page 201: ...FIG 3 AC DC POWER SUPPLY s TYPE 422 AC DC FIG 3 ...
Page 205: ......