Tektronix 434, Instruction Manual

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O perating In s tru c tio n s —434
5 MHz BW
IN V E R T
(CH 2 o n ly)
G A IN
A push-push sw itch th a t lim its the
com plete vertical a m p lifie r system
b a n d w id th
to a p p ro x im a te ly 5
MHz.
A push-push switch to in ve rt the
Channel 2 display.
Screw driver adjustm ent to set the
gain o f the vertical a m p lifie r.
algebraic sum is displayed on the
C RT. The IN V E R T sw itch in
Channel 2 allows the display to
be CH 1 + CH 2 or CH 1 - CH
2
.
CHOP: Dual-trace display o f signals
on both channels. Display
sw itched at a re p e titio n rate o f
a p p ro xim a te ly 100 kH z.
STEP A T T E N B A L S crew driver adjustm ent to balance
the in p u t a m p lifie r in the 1 m V , 2
m V , 5 m V , and 10 m V positions o f
the V O L T S /D IV switches.
In p u t C oupling Selects m ethod o f co upling in p u t
(A C /D C , G ND) signal to in p u t a m p lifie r.
A C : In the AC position (b u tto n in)
o f this push-push sw itch, signals
are capacitively coupled to the
vertical
a m p lifie r. The DC
c o m p o n e n t o f the in p u t signal is
blocked. Low frequency —3 dB
do w n p o in t is a bout 10 hertz.
CH 2: Displays Channel 2 o n ly.
Triggering
SOURCE Selects source o f trigger signal.
CH 1: A push b u tto n sw itch th a t in
the CH 1 p o sitio n (b u tto n in)
selects CH
1 as an internal
trigger source.
COMP: A p u sh b u tto n switch th a t
in the COMP po sitio n (b u tto n
in) allow s the internal trigger
source to be determ ined by the
vertical m ode o f ope ra tio n .
CH 1 and CH 2
In p u t
Mode
(N o t labeled)
DC: In the DC position (b u tto n
o u t) o f the AC push-push
sw itch, all com ponents o f the
in p u t signal are passed to the
in p u t a m p lifie r.
G N D : In the GND p o sitio n (b u tto n
in) o f th is push-push sw itch , the
in p u t o f the vertical a m p lifie r is
disconnected fro m the in p u t
connector and grounded. A llo w s
precharging
o f the in p u t
co upling capacitor.
In p u t connectors th a t allow
a p p lica tio n o f external signals to
the inputs o f the vertical a m p lifie r.
Includes a coding ring fo r probes
w ith scale fa c to r sw itching.
Selects mode o f op e ra tio n fo r
vertical in p u t am plifiers.
CH 1: Displays Channel 1 o n ly.
A L T : D ual-trace display o f signals
on b o th channels. Display
sw itched between channels at
the end o f each sweep.
E X T A T T E N
C O U PLIN G
A D D : Signals applied to the CH 1
and CH 2 In p u t connectors are
algebraically
added and the
L IN E : When b o th the CH 1 and
COMP switches are pressed in, a
p o rtio n o f the line frequency
voltage is used as a trigger signal.
E X T : When both the CH 1 and
COMP switches are o u t, signals
applied
to the E X T T R IG
connector are used fo r
triggering.
In the 1:10 p o sitio n (b u tto n in) o f
this push-push sw itch , external
trigger signals are attenuated by a
fa c to r o f 10. In the 1 :'1 position
(b u tto n o ut) external trigger signals
are n o t attenuated.
Determ ines m ethod o f coupling
trigger signal to trigger c irc u it.
A C : In the AC po sitio n (b u tto n in)
o f th is push-push sw itch, DC is
rejected and signals below about
20 hertz are attenuated. Accepts
signals between a b o u t 20 hertz
and 25 megahertz.
DC: When b o th the AC and the LF
REJ push-push switches are o u t,
signals are d ire c tly coupled to
the trigger c irc u it. Accepts all
signals fro m DC to 25 megahertz
2-3