Tektronix 7a11 Instruction Manual page 66

b. Connect t h e 7 A 1 1 Probe (thr ough
t
he 50 Ω Termina-
tion and th e 10Χ Attenuator) to the Type 106 + O utput
conn ector.
ε. Set the Ty pe 106 Sq ua re
W
ave Gene rator freque ncy
to 25 kH z and
a
djust t h e + Transition Amplitude to obtain
5 divisions se paration
b
etween
t
he two traces on the
7000-Series Oscilloscope C RT. Ce nter the two-trace display
on the 7000-Series Oscilloscope,
u
sing the 7 A 1 1 and Time
Base Position controls.
d. Adju st the Sampli ng System as necessary to obtain α
stable display. (Time Base at 10 μs/
d
iv, bot h chan nels of
the 3S1 at 50 mV/
d
ivision.)
e. CHE CK-T rigger ci rcuit outpu t amplitude. The dis-
play am plitude on the Sampli n
g System CRT should be 5
(±0.5)
d
ivisio ns.
19 .
Ch ec k Trigger Circuit Transient
R
esponse
(C295)
α. The setu
p
is co n tinue
d
from steps 15 throug h 18 . Α
sq
uare wave (from th e Ty
p
e 106) is being
d isplayed (t hroug h
t
he 7Α11 trigger-signal circuit an d Extender) on the Sampl-
ing System CRT.
b. Switch
t
he 7Α11
V OLTS/DI V to 50 mV and the
Bandwidth to FULL .
RE QU I REMENT: Aberrations within ±6°/ ο, (10% peak-
to-pea k).
ε. Set the Sam
p
ling System sweep rate to 10 ns/div .
d.
R
emove the 10Χ Attenuator from the signal
p
ath.
e. Ad just the Ty
p
e 106 Square
W
ave Generator + Transi-
tion Amplitu
d
e to o btain exactly 5
d
ivisions dis
p
lay
am plitud e on th e Sampling System . Then adj ust the 7 A 1 1
P
OSITIO N control,to ce nter the
d
isplay .
f. C HE C K- :Aberrations on the Sampling System
d
isplay
sh oul d b e with in ±0 .3
d
ivisions, (0 .6 divisions peak-to-
pea k).
20 . Chec k Trigger Signal
R
isetime
REQU I REMEN T:
R
isetime should be with in 2.1
n
s.
Performance Check/Calibration-7A71
α.
T he setup is co nti nued from steps 15 through 19. Α
centere
d
5
d
ivisio n
d
is play (from the Type 106) is
b
eing
d
isplayed (t hro ugh
t
he 7 A 1 1 trigger-circuit an
d
Exte nder)
on th e Sampling System CR T.
b .
Center the
d
isplay on the Sampling System CRT,
using the 7 A 1 1 POSITION control .
ε. Select 500 ps sweep rate at the Sampling System Time
Base an
d
center
t
he display, simila r to that in Fig. 5-11 .
d.
M
easure the trigger signal risetime
b
etween
t
he 10%
an d 90% amplitude levels as in
F
ig . 5-11 .
e. Determine the
p oi n t at wh ic h th e risetime intercepts
the Ty pe 106-3S1 risetime on t he graph in
F
ig. 5-18 .
ns .
f. CHE CK-Trigger signal risetime should not exceed 2.1
g. Disconnect the Probe, Termination an
d
10 Χ Attenua-
tor from the Ty pe 106 S
q
ua r e
W
ave Ge nerator.
21 . C hec k Trigger Circuit
F
re
q
uency
R
es
p
onse
(O
p
tional ste
p
- see NOTE)
RE QU I REMENT : At least 167 MHz at the -3 dB
p
oint .
NO ΤΕ
R isetime an d
f
requency
r
esponse (bandwidth) are
r
elatedas follows:
tr
--
0.35
b
w
T h e 2.1 ns
r
isetime verified in step 20 indicates α
f
requency response of at least 167 MHz.
α. Control settings given i n Table 5-2 apply except that
the 7A 11 VO LTS/DI V switch is at 50 mV . The 7A 11 trig-
ger circ uit is connecte d (through the Plug-in Extende r) to
the Chann el Α and Β in
p
uts of the 3S1 .
b. Connect the 7 A 1 1 Probe, 50 Ω Te rmi nation , and α
10 Χ G R Attenuator to the Output connector on the
067-0532-00 Constant Am plitu
d
e Signal Generator (item
7) .
ε . Set the Signal Generator Frequency
R
ange to 3 MHz
an d
a
d
just its Amplitud e controls to obtain an 8 division
display on the Sampling System CRT.
5- 25