Tektronix 434, Инструкция по эксплуатации

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C a lib ra tio n —434
c. C H E C K —S hould n o t be able to p o sitio n the free-
running trace o u t o f the graticule area w hen holding the
BEAM F IN D E R b u tto n in.
15. Check External Z A x is Operation
a. C o n n ect the o u tp u t o f the M edium -Frequency
C o n sta n t-A m p litu d e Signal Generator to the E X T T R IG
and Z A X IS in p u t connectors via a 50 £2 te rm in a tio n , a
BNC T , and tw o 42-inch 50 £2 BNC cables.
b. A d ju s t the C onstant—A m p litu d e Signal Generator fo r
a 5 -v o lt o u tp u t am p litu d e o f 50 k ilo h e rtz reference signal.
c. Set the T IM E /D IV sw itch to 20 jus and the T R IG G E R
SOURCE to E XT.
d. A d ju s t the T R IG G E R L E V E L c o n tro l fo r a stable
display.
e. C H E C K —C R T display fo r noticeable in te n s ity m o d u ­
la tio n o f the trace (m ay require reducing the setting o f the
IN T E N S IT Y c o n tro l).
f. Increase the o u tp u t frequency o f the C onstant
A m p litu d e Signal Generator to 20 megahertz.
g. Set the T IM E /D IV sw itch to .05 jus.
h. C H E C K —C R T display fo r noticeable in te n s ity m o d u ­
la tio n o f the trace.
i. D isconnect all test equipm ent.
16. Check Chopped Operation
a. Set the T IM E /D IV sw itch to 2 jus and the T R IG G E R
SOURCE to COMP.
b. A p p ly 1 jus tim e marks to the CH 1
in p u t
connector.
c. A d ju s t the T R IG G E R L E V E L c o n tro l fo r a stable
display.
d. A d ju s t the T IM E /D IV sw itch and the Variable T IM E /
D IV c o n tro l fo r e xa ctly tw o markers per division.
e. D isconnect the T im e-M ark Generator. Do n o t change
the setting o f the T IM E /D IV sw itch o r the Variable T IM E /
D IV c o n tro l.
f. Set the V ertical Mode to CHOP.
g. A d ju s t the T R IG G E R L E V E L c o n tro l fo r a stable
display.
h. A d ju s t the CH 1 and CH 2 PO SITIO N c o n tro ls to
separate the tw o traces.
i. C H E C K —T im e d u ra tio n o f chopped w aveform should
be a p p ro xim a te ly 4.2 to 6.2 divisions (80 k ilo h e rtz to 120
k ilo h e rtz , a p p ro x im a te ly ).
NOTES