Tektronix 1L30, Instruction Manual

Page: 51 / 129

fl1ri^1~tV^^‘,^ ^ ' l^ ^ ' ;*i°v
Perform ance Check— Type 1L30
Fig. 5-1. Measuring dispersion accuracy.
must remain within listed specifications given in Table 5-1, to
the + and — 25 M H z positions.
g. Center the coarse IF CENTER FREQ control. Set the
DISPERSION control to 1 M Hz position and apply 10 ns and
1
/
a s
markers from the Time-Mark Generator.
h. Check— The range of the IF CENTER FREQ-FINE control.
Must equal or exceed + and — 1 M Hz from its centered
position.
i. Return the VERTICAL DISPLAY switch to the LIN posi­
tion.
Fig. 5-2. Measuring dispersion linearity.
3. Check Resolution Bandwidth
a. Requirement— Resolution bandwidth - is variable from
1 kHz or less to 100 kHz or more.
b. Apply 200 M Hz signal from the Time-Mark Generator
to the RF INPUT connector through a 20 dB attenuator.
Switch in 20 dB of IF Attenuation on the Type 1L30. Tune
the RF CENTER FREQ control to minimize interference of
the converted signals (tunable signals).
c. Set the DISPERSION RANGE to kH z/C M position and
the DISPERSION to lOOkHz/cm. Uncouple the RESOLU­
T IO N and turn the control fully clockwise. Set the Time/Cm
selector to .1 s.
N O TE
If a Type 5 4 9 storage oscilloscope is used, set the
controls fo r single sweep storage and a fte r sweep
autom atic erase.
d. Adjust the G A IN control for a 6 centimeter display
amplitude.
e. Check the resolution bandwidth response of the Type
1L30 to the 200 M H z signal at the — 6dB points. To check
P
jf
r
TABLE 5-1
DISPERSION
Position M arke r Selection M a rk e rs /C m
A llo w a b le
Error
S upplem entary
Notes
10 MHz
1 0
ns
a n d .1 /
as
1
± 3 %
5 MHz 10 ns
a n d .1
[is
1 m a r k e r /
2 cm
± 3 %
Over the range of the IF
CENTER FREQ control
2 MHz 10 ns
a n d
.5 [is
1
± 5 %
1 MHz
1 0 ns a n d 1 /
as
1 ± 5 %
( ± 2 5 MHz).
.5 MHz
1 0 ns a n d 1
[is
1 m a r k e r /
2 cm
± 1 0 %
.2 M Hz
10
ns a n d
5
/as
1
± 1 5 %
D is p la y lin e a r it y o v e r
a
10 c e n tim e te r d i s p l a y
m ust b e w it h in ± 3 % .
© 5-3 i
t:
fi.;