Tektronix 1L30, Инструкция по эксплуатации

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i C alib ratio n — Type 1L30
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Fig. 6-14. Location of kHz/CM dispersion adjustments.
( 1 ) A p p ly a ca lib ra ted 100 M H z RF signal to
the RF input o f the Harm onic M o d u lato r (Test
Fixture 0 6 7 - 0 5 1 8 - 0 0 ) from the Signal G enerator.
) ( 2 ) A p p ly a 5 0 0 kHz signal to the Mod Freq
| 1 input connector o f the Harmonic M o d u lato r from
| an accurate A udio Signal G en erato r.
| ( 3 ) Connect the M od Harm O ut connector through
| a 1 0 X atte n u ato r to the RF INPUT connector of
| the Type 1L30.
| This w ill provide an IF feedthrough signal o f 2 0 0
M H z m odulated by the Audio Signal G enerato r
frequency.
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| 7. Check Dispersion Accuracy of k H z/C M
j Ranges
I ■ . .
I a. Test equipment setup is given in step 6.
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b. Set the DISPERSION selector to 500. Depress the 10
ns and
1 /
as
Marker Selector buttons on the Time-Mark
Generator.
c. Check the frequency range of the IF CENTER FREQ
control. Frequency range must equal or exceed + and —
2.5 M Hz from its centered (000) position.
d. Center the coarse IF CENTER FREQ control. Set the
DISPERSION selector to 50kH z/cm .
1 e. Check the frequency range of the IF CENTER FREQ-
| FINE control. Frequency range must equal or exceed +
\ and — 50 kHz from its centered position.
f. Set the DISPERSION selector to the 500 kHz position
^ and center the IF CENTER FREQ controls.
\
g. Check dispersion accuracy through + and — 2.5 MHz
I change in the IF center frequency, at each DISPERSION
selector position listed in Table 6-2.
(A ) 1 m arker/2 centimeter (Checking 500 kHz/CM disper­
sion.) Center marker is 200 MHz feedthrough.
(B) 1 marker/centimeter. (Checking 100 kHz/CM disper­
sion.)
Fig. 6-15. Typical displays when checking or adjusting kHz/CM
dispersion.
Dispersion accuracy must remain within ± 3 % . (2.4 milli­
meters) for all DISPERSION selector positions.
As the dispersion is decreased the sweep time should be
increased (slower sweep rate) to maintain optimum resolu­
tion.
Uncouple the RESOLUTION control and adjust for
optimum time marker definition. The VIDEO FILTER may
improve the marker definition at the narrow dispersion set­
tings.
TABLE 6 -2
T im e-M ark
D isp lay in
DISPERSION G e n e ra to r
centimeters
kH z/c m
M a rk e r Selector
per m arker
500
10 ns and 1 /is
2
200 10 ns and 5
/
as
1
100
10 ns and 10
/
as
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1
50
10 ns and 10 /.is 2
20
10 ns and 50 /is
1
10
10 ns and .1 ms 1
5
10 ns and .1 ms
2
(Turn VIDEO
FILTER on)
2
10 ns and .5 ms
1
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