Tektronix 434, Instruction Manual

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O perating In s tru c tio n s —434
E N H A N C E L E V E L Provides a selectable increase in
w ritin g speed c a p a b ility fo r single­
sweep displays. E ffective o n ly when
e ither o r b o th E N H A N C E push-
b u tto n s are depressed.
IN T E G R A T E A p u sh b u tto n switch th a t perm its
s to r a g e o f very fast re p e titive
signals by allow ing the w ritin g -g u n
beam to accum ulate charges on the
target w h ile the flood-gun beams
are turned o ff.
N O T E
The setting o f the A S T IG a d ju stm e n t sho u ld be
c o rre c t fo r any display. However, fin e a d ju stm e n t o f
A S T IG fo r a specific IN T E N S IT Y setting m ay be
desirable.
1. C onnect the o u tp u t o f the PROBE C A L 0.6 V 1 kH z
jack to either channel in p u t and set the V O L T S /D IV switch
o f th a t channel to present a three-division display. Set the
vertical M ODE sw itch to display the channel selected.
LO C A TE A p u sh b u tto n switch th a t unblanks
the CRT and provides a visible in d i­
cation o f the p o sitio n o f the display
signal w h ile the sweep is held o ff.
This perm its the display to be posi­
tioned before storing.
2. Set the T IM E /D IV sw itch to .5 ms.
3. A d ju s t the IN T E N S IT Y c o n tro l to the desired
setting.
C alibrator
PROBE C A L Provides a 0.6 v o lt ca lib ra to r signal
0.6 V 1 kH z to p e rm it probe com pensation,
adjustm ent o f a m p lifie r G A IN , and
checking basic h o riz o n ta l tim in g .
Power and External Blanking
POWER and A co m b in a tio n c o n tro l, p a rt o f
IN T E N S IT Y w hich is a push-pull sw itch to
c o n tro l app lica tio n o f pow er to the
in s tru m e n t.
4. Set the A STIG a d justm ent so the h o rizo n ta l and
vertical p o rtio n s o f the display are as equally focused as
possible.
Trace A lig nm en t A djustm e n t
If a free-running trace is n o t parallel to the h o rizo n ta l
graticule line, set the T R A C E R O T A T IO N adjustm ent (rear
panel) as fo llo w s . Position the trace to the center h orizontal
line. A d ju s t T R A C E R O T A T IO N so the trace is parallel
w ith the h o rizo n ta l graticule line.
Z A X IS In p u t connector fo r external
blanking signals.
G E N E R A L O P ER A TIN G IN F O R M A T IO N
Inte n sity C o n trol
The setting o f the IN T E N S IT Y c o n tro l should n o t a ffe ct
the co rre ct focus o f the display. The focusing c o n tro l is
ganged to the IN T E N S IT Y c o n tro l to provide a utom atic
adjustm ent o f display focus along w ith adjustm ent o f
display in te n s ity .
The lig h t filte r and o p tio n a l EMI mesh filte r reduce the
observed lig h t o u tp u t fro m the C RT. When using these
filte rs , avoid advancing the IN T E N S IT Y co n tro l to a setting
th a t could cause phosphor damage. When the highest
in te n sity display is desired, remove the filte rs . A pp a re n t
trace in te n s ity can also be im proved in such cases by
reducing the am bient lig h t or using a viewing hood.
Astigm atism A djustm e n t
If the CRT display is n o t w ell-defined, adjust the A S T IG
(rear panel) as fo llo w s .
G raticule
The graticule o f the 434 is in te rn a lly marked on the
faceplate o f the CRT to provide accurate, no-parallax
measurements. The graticule is marked w ith eight vertical
and 10 h o rizo n ta l divisions. Each division is .98 centim eter
square. In a d d itio n , each m ajor division is divided in to five
m in o r divisions at the center vertical and h o rizo n ta l lines.
The vertical gain and h o riz o n ta l tim in g are calibrated to the
graticule so accurate measurements can be made fro m the
C RT.
Fig. 2-3 shows the graticule o f the 434 and defines the
various measurement lines. The te rm in o lo g y defined here
w ill be used in all discussions involving graticule measure­
ments.
Lig ht F ilte r
The tin te d lig h t filte r provided m inim izes lig h t reflec­
tio n s fro m the face o f the CRT to im prove co n tra st when
viewing the display under high am bient lig h t co n d ition s.
The mesh filte r (available as an o p tio n a l accessory) provides
shielding against radiated EMI (electro-m agnetic in te r­
ference) and also serves as a lig h t filte r. T o remove either
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