Tektronix 323, Инструкция по эксплуатации

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Operating Instructions— Type 3 2 3
generator frequency until the trace disappears and then note
the frequency. (The triggering circuit half-power point oc­
curs at approximately 16 Hz during AC-coupled operation.)
25. Switch the Trig/Horiz Coupling control to DC, and the
TIME/DIV control to .2 mS. Note that the trace re-appears.
Decrease the signal generator frequency to 2 Hz. Note that
a stable trace remains. (Readjust the TRIGGER Level if
necessary.) When DC coupling is selected and the TRIG­
GER control is not at AUTO, a trigger can be generated
whenever the EXT TRIG OR HORIZ INPUT voltage passes
through the DC value selected by the TRIGGER Level con­
trol, even though the transition is made very slowly. If
the signal has a DC bias, the trigger point will be influ­
enced by that bias.
26. Switch the TRIGGER control to + AUTO. Note that
the trace becomes unstable. The trigger input becomes AC-
coupled whenever the TRIGGER control is at AUTO, regard­
less of the setting of the Trig/Horiz Coupling lever. The
2 Hz signal frequency is too low to cause AC-coupled trig­
gering to occur. Increase the generator frequency to 60
Hz and note that the display becomes stable, indicating that
the sweep is again being triggered by the input signal.
27. Disconnect the signal from the EXT TRIG OR HORIZ
INPUT connector. Switch the Trigger Coupling lever to INT
TRIG ACLF REJ. Note that the trace is again unstable.
Change the generator frequency to 10 kHz and note that the
trace stabilizes. ACLF REJ greatly reduces circuit sensitiv­
ity to internal trigger signals of approximately 10 kHz and
lower, to prevent low-frequency signals from randomly trig­
gering the sweep while high frequency signals are being
observed.
XY Operation
NOTE
Whenever the Type 323 Oscilloscope is operated
in EXT HORIZ mode, the CRT is unblanked and no
internal sweep is available. If no input signal is
present at the vertical or horizontal input connector,
a bright stationary dot w ill appear. It is recom­
mended that the brightness be reduced to provide
an intensity which is consistent w ith good viewing.
Decreasing beam intensity w ill also increase b a t­
tery-operating time.
28. Reconnect the signal generator output to the EXT TRIG
OR HORIZ INPUT jack. Switch the TIME/DIV control to EXT
HORIZ and the Trig/Horiz Coupling lever to EXT TRIG OR
HORIZ-AC. The straight diagonal line rising as it progresses
from left to right is indicative of in-phase conditions existing
between the signals at the vertical and horizontal input con­
nectors. The deflection along the vertical and horizontal
coordinates is dependent upon the amplitude of the re­
spective input signals and the deflection factors involved.
29. Rotate the EXT HORIZ VAR counterclockwise from CAL
and note that as the horizontal gain decreases, the slope
becomes greater. Return the EXT HORIZ VAR to CAL.
30. Switch the EXT TRIG OR HORIZ ATTEN to X10.
Observe that the horizontal deflection is reduced to 1/10 of
its previous amount.
31. Reset controls as follows:
EXT TRIG OR HORIZ
ATTEN
VOLTS/DIV
INPUT
X 1 0 VERT GAIN
X 1 0 HORIZ MAG
TIME/DIV
TRIGGER
Trigger Coupling
X I
5 DIV CAL
GND
in
in
.2 ms
+ AUTO
INT TRIG AC
Adjust the POSITION controls until the square wave again
appears on the CRT.
32. Disconnect the cables from the VERT INPUT and EXT
TRIG OR HORIZ INPUT connectors.
Power Supply Operation
33. Switch the Power Pack switch to FULL CHG. Note that
no change occurs in the presentation.
34. Disconnect the AC source from the Oscilloscope. Again
note that no change occurs in the presentation.
35. Connect the Oscilloscope to an external DC voltage
of between 6 and 16 V, using two leads equipped with
banana plugs. Make the proper polarity connections. Re­
verse connections will blow the high voltage fuse. Switch
the Power Pack switch to EXT DC. Again, note that there is
no apparent change.
36. Switch the POWER control off and the Power Pack
switch to FULL CHG. Disconnect the Oscilloscope from the
DC power source and reconnect the AC power input to an
appropriate AC voltage supply. Retain this condition for
16 hours to obtain a full battery charge.
The First-Time Operation procedure has been completed.
After 16 hours have elapsed, switch the Power Pack switch
to TRICKLE CHG to maintain the fully charged battery con­
dition.
OPERATOR’S CHECK
A N D ADJUSTMENT PROCEDURE
The following characteristics of the Type 323 Oscilloscope
should be checked prior to each period of operation. Access
to screwdriver adjustments are provided through the bot­
tom panel to permit the operator to optimize the instru­
ment’s performance. Perform the checks and adjustments
in the sequence provided to avoid interaction.
CAUTION
Use a loose fittin g screwdriver to make the adjust­
ments. Do not a p p ly excessive force.
Preliminary Procedure
Set the Type 323 Oscilloscope controls as follows:
2-12
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