Tektronix R7613 Instruction Manual page 10

Operating Instructions-7613/R7613 Operators
5 . Set both vertical units for a deflect ion factor of two
volts /division and center the vertical posit ion co ntrols. Set
both ve rtical un its for AC input coup ling .
6 . Set t h e time-base u nit for a sweep rat e of on e
m illisecond /d ivision in the auto , int ernal t rigge r mode .
7. Adva nce t h e INTENSI TY co ntro l u ntil the tr ace is at
the desired viewing level (near rnidranqe
l.
Adva nce th e
R EADOUT until t h e read o ut displa y is at t h e desired
view ing level.
8. Conneet th e 4 V calibrator pi n-jack to t h e in put of
the left verti cal u nit w ith a BNC t o p in-jack cab le (sup plied
accessory ).
Display Focus
9. Adjust the FOCUS adjustment for a sha rp ,
we ll-defined d isplay over t h e entire t race length. lf a
properly focused disp lay cannot be obtained w ith t he
FOCUS ad justment, the int e rn a l Astigmatism adjustment
must be rese t ; see t he Cal ibration section of the Service
manual.
Trace Alignment
10. Disconnect the input signal and positron the trace
with the left vertical un it pos it ion control so it coincides
with the center horizontal line of the graticule. If the trace
is not parallel to the center horizontal line of the graticule ,
see Trace Rotation adjustment procedure in Calibration
section .
Graticule IIlumination
11. Rotate the GRATICULE ILLUM contro l th rough-
out its range and not ice that the ilium ination o f the graticu Ie
lines increases as the control is turned clockwise (most
obvious with tinted f ilter installed). Set the control so the
gra ticule lines are illum inated as desired.
Vertical Deflection System
12 . Con neet the 4 V calibrato r signa l to the input
con nector of t h e left ve rtica l unit with t h e BNC to pin -jack
cabie . Set bo th vertical un its for a deflection factor of one
volt/div isio n. T he displa y ampli tude should be four
div isions . Note th e exact dis p lay am p litude for step 15.
13 . Notice that the posrtion control of only t he left
ver t ical un it has an effect on the po sition of t he d isp lay.
Position the display to the uppe r ha lf of the grat icu le.
1-6
14 . Press the RIGHT button of the VERT MODr
switch. Remove the calibrator signal f ro m the left vertica
and conneet it to the right vertical. The display arnplitudr
should be four divisions within 0.12 d ivision. Note the
exact display ampl itude fo r the next step.
15. A cor rect d isp lay in bo th steps 12 and 14 ind icat es
that the 7613 Vertical Deflection System and the vertical
plug-in u n its are cal ib rated . If the displays no t ed previously
are both ou tside the give n t o lera nee in the same direction
(i.e ., high or lo w) , t he Ve rtical Gain or 4 Volts calibrator
adjustment probably needs re-adj ust me nt. Otherwise, check
t h e calibration of t h e vertica l p lug-in un its .
16. No tice that the posr t ro n control of only t he right
vert ical u nit has an effect on t h e pos ition of t he display.
Positio n the display to the lo wer ha lf of the graticule. Set
both vertical units for a deflection factor of two
volts/division. Conneet the calibrator signal to both vertical
units by using a dual input coupie r.
17. Press the ALT button of the VERT MODE switch.
Notice that t w o traces are displayed on the CRT. The top
t race is produced by the left vertical unit and the bottom
trace is produced by the right vertical unit. Set the sweep
rate to 50 milliseconds/division . Notice that the display
alternates between the left and right vertical units after
each sweep. Turn the sweep rate switch throughout its
range. Notice that the display alternates between vertical
units at all sweep rates.
18. Press the CHOP bu tton of the VERT MODE switch.
Turn the sweep rate throughout its range. Notice that a
dual -trace display is presented at all sweep rates, but unlike
ALT both vertical units are d isplayed on each sweep in a
time-sharing manner . Return the sweep rate to 0.5
m illisecond /division.
19. Press the ADD button of the VERT MODE switch.
The display should be the algebraic sum of both signais.
Notice that the position control of either vertical unit
moves the display . Return the VERT MODE switch to
LEFT.
Triggering
20 . Ce nter the display o n the CRT with the left vertical
u n it pos itio n contro\. Disconnect the input signal from the
right vertica l u nit input co nnector . Sequentially press all of
t he VERT MODE sw itch bu ttons. Notice that a stabie
d isp lay is obtai ned in all posit ions of the VERT MODE
swit ch (stra ight line in R IGHT pos it io n) .
®