Tektronix 535 Manual

TYPE 535
Serial Numbers 101 through 60kk
SUGGESTED FACTORY CALIBRATION PROCEDURE
Preset front-panel controls as follo s:*
POWER SWITCH— OFF.
Main S eep TRIGGERING LEVEL— 0.
" » STABILITY— CCW.
TRIGCER SLOPE— *INT.
TRIGGERING MODE— AC SLOW.
TIME/CM— 10 milli sec.
MULTIPLIER— XI.
5X MAGNIFIER— OFF.
HORIZONTAL DISPLAY— MAIN SWEEP NORMAL.
Delaying S eep TRIGGERING LEVEL— 0.
» » STABILITY-CCW.
SLOPE (toggle)— *.
ATTEN. (toggle)— XI.
TIME/CM OR DELAY TIME— 1 millisec
HORIZONTAL POSITION— MS.
VERNIER— MS.
CALIBRATOR— OFF.
INTENSITY— CCW.
Preset R6U to CW, (This is a small scre driver-slotted potentiometer con
trol ithout shaft, situated at right center of top deck.)
Preset DELAY STOP ADJ to about 30° from CCW stop.
The follo ing controls may be left at the settings here they are found—
that is, they do not require presetting: (l) CAL ADJ, and (2) R99M— the latter
being a small scre driver-slot control mounted on the MULTIPLIER s itch bracket.
Preset the remaining fourteen internal scre driver-slotted controls to MS.
Preset the follo ing capacitors to MS: C2h0 , C2Sh> C278, C286.
With no plug-in unit in position, check the resistances to ground of the
lo voltage po er supplies. (While no tolerances are specified, it may be stated
as a general guide that the resistance of the -1^0-volt supply usually runs in the
neighborhood of I;,000 to 5,000 ohms. The resistances of the remaining supplies
are progressively higher as you go to more positive voltages. The 500-volt sup
ply might be expected to have a resistance of about 50,000 ohms.) If any t o sup
plies appear to have the same resistance values, you should check for a possible
short circuit bet een them.
Carry out the follo ing calibration procedure:
1. To check relay time delay.— Remove high-voltage oscillator tube V803 (6AU5).
With po er-test plug-in unit in position, turn POWER s itch on. Check that
the time required for the relay to operate lies bet een 15 sec and U5 sec.
(The thermal time-delay relay, K700, is rated for a U5-sec delay hen 6
volts are applied to it. In the interest of positive contact operation, the
relay is actually operated ith about 9 volts applied, and the operating time
may be appreciably less than U5 sec as a result.) Observe by the flickering
of neon lamp NE95, located above VbO on the s eep chassis, that the main s eep
■“•Front-panel controls are indicated by UNDERLINED CAPITALS. Internal adjustments
are indicated by PLAIN CAPITALS. These abbreviations are used: CW, clock ise;
CCW, counter-clock ise; MS, mid-scale.
August, 1956 FD-535-1
Revised
November, i960

operates hen you turn the Main S eep STABILITY control CW. This flicker is
readily discernible hen the s eep operates at the 10-millisec/cm rate.
(With the main s eep operating, it is probably safe to apply the high volt
age to the CRT even if there should be a iring defect in the circuits affecting
the spot intensity.)
Turn the FOCUS and ASTIGMATISM controls CW. With the Main S eep operating as
above, insert the high-voltage oscillator tube, and observe that the trace can
be turned on and off by means of the INTENSITY control. No set the TIME/CM
control to 100 Msec.
2. To check lo -voltage po er-supply operation.
a. With 117 line volts applied, give a quick check to each lo -voltage supply
to determine that it is delivering approximately the correct voltage. This
quick check helps to reveal overloads or other gross irregularities in oper
ation.
b. Set the -150 VOLTS ADJ control for precisely 150 volts output from the -150-
~ volt supply.
c. Check that the +100-volt supply delivers its rated output voltage ithin ±2%,
Check that the +225-volt, +350-volt and +500-volt supplies deliver their rated
voltages ithin ±3%» (For satisfactory operation of the vertical amplifier, the
350-volt supply must usually deliver at least 345 volts.) If a po er-supply
voltage falls outside these tolerances, proceed as follo s:
(1) Check that the supply affected is regulating (Part e belo ).
(2) If a supply regulates, but if the voltage falls outside the tolerances
given above, see that the supply is properly ired and tubed. In par
ticular, see that normal screen voltages are applied to hichever of
these tubes is involved in the affected supply: V700, V742, V757> V782
or V791. (See DC VOLTAGE MEASUREMENTS pamphlet.)
(3) Try a different comparator tube ( hichever of these tubes is involved in
the affected supply: V712, V742, V765, V782 or V79l).
(4) Try a different set of precision resistors in the voltage divider in the
affected supply.
(5) Finally, if the above steps fail to bring the voltage ithin tolerance,
install a l/2- att composition resistor beneath one or the other of the
precision resistors in the voltage divider of the affected supply. Use
a composition resistor of such value (usually several megohms) that the
supply voltage is brought ithin the tolerance range.
d. Set the test oscilloscope* for a s eep speed of 1 millisec/cm and the s eep
speed multiplier to X5. Set the vertical sensitivity to 0.005 volts/cm.
Using a 2X probe, determine that the po er-supply ripple does not exceed
10 millivolts for the -150-volt, +100-volt ana +225-volt supplies, and
that the ripple does not exceed 15 millivolts for the +350-volt and the +500-volt
*It is assumed that a Type 531 test oscilloscope is used.
August, 1956 FD-535- 2

supplies. These ripple measurements are to be made at the po er-supply
output connections on the bottom deck of the oscilloscope. (The ripple
voltages are usually appreciably smaller than the above outside tol
erances. In particular, if the ripple on the -150-volt supply or on the
+100-volt supply exceeds 3 or U mv, one should suspect a defective com
ponent or a iring error. If components and iring are good, ho ever,
the above tolerances apply.)
The predominant ripple frequency should be 120 cps, rather than 60 cps.
This is evidenced by a display of approximately six cycles over the grat
icule of the test oscilloscope, hen the s eep rate is 5 millisec/cm as
set above.
e. Check the po er-supply regulation by observing that the ripple voltages on
the various supplies do not exceed approximately the tolerances given in
Part d, above, as the line voltage and the loads are varied. Supplies must
remain in regulation ithin the follo ing operating limits:
Lo er limit— line volts, 105>; plug-in set at HI load.
Upper limit— line volts, 125; plug-in set at L(5 load.
NOTE:— If a supply fails to regulate, this failure may be caused by too
small or too large a load, traceable to defective s eep circuits, vertical
amplifiers, or other portions of the oscilloscope. In event of regulation
trouble, do not confine your efforts to the affected supply, but make an
effort to get all other parts of the instrument into approximately correct
operation before deciding that the trouble is centered in the po er supply.
3. To set CAL ADJ.— -Use 117 line volts. With red calibrator knob turned to the
OFF position, set CAL ADJ (bottom front of oscilloscope) for +100 volts at
Pin 3 of V2i*6 (best checked at the connection from that pin to the calibrator
attenuator). The voltage at this point should drop to not more that +55 volts
but not less than +k$ volts hen the red calibrator knob is turned to the
MILLIVOLTS or to the VOLTS position, ith the black calibrator knob in any
position, (This last reading is to assure suitable calibrator symmetry,)
lu To ad.just and check high-voltage supply.—
a. Observe that the high-voltage rectifier tubes are all lighted. If the
"" brightness of the filaments is much different from one tube to another in
the high-voltage supply, consider changing the high-voltage po er trans
former. Replace any high-voltage rectifiers exhibiting a blue glo bet een
the elements, or having the glass cracked around the seals.
b. Set the -1350-volt output of the high-voltage supply to its rated value ith
the HV ADJ control. (Measure bet een the -l50-volt supply output, and the
first left-hand terminal of the ceramic strip adjacent to the CRT GEOM ADJ
control. Use the 1200-volt range on the voltmeter.)
c. Check regulation of the -1350-volt output bet een these limits:
August, 1956 FD-535-3

Lo er limit— line volts, 105; INTENSITY advanced to produce a (defocused)
spot or glo .
Upper limit— line volts, 125; INTENSITY at CCW, to produce no spot.
The regulation is observed by noting that the voltmeter reading remains
nearly constant.
IMPORTANT— The above tests and adjustments are the ones normally required.
Note that they do not directly indicate correct operation of the -lU50-volt
and the +8650-volt portions of the high-voltage po er supply. If the
-Uj50-volt portion of the supply is not operating correctly, you may have
trouble in turning the spot off ith the INTENSITY control, particularly
hen the s eep is operating; or you may experience trouble in obtaining a
spot at all, particularly hen the s eep is not operating. In cases of
these kinds, you should also measure the -lU50-volt output of the supply.
If the +8650-volt output is not operating correctly, the trace may not dis
play normal brightness on the fastest s eeps, even ith the INTENSITY control
turned ell up. An even more important result of improper voltage from the
+ 8650-volt output is the effect upon horizontal and vertical deflection sen
sitivity. It must al ays be kept in mind that trouble ith timing or ith
vertical gain might be due to incorrect operation of the +8650-volt supply
circuits, rather than to the horizontal or vertical deflection systems. In
some cases, it may be desired to measure the +8650-volt output, using t o
voltmeters in series; but you should remember that the loading effect of the
measuring circuit can affect the reading.
5. To check s eep and vertical systems for operation.— Use 117 line volts.
a. Bring up INTENSITY control slo ly from CCW position until a spot or glo
appears on screen. Position spot on screen, keeping INTENSITY setting at
minimum useful point. Bring up Main S eep STABILITY control from CCW position
until s eep is produced. Adjust FOCUS, INTENSITY and ASTIGMATISM controls to
produce a trace of suitable sharpness and intensity.
b. Push CRT for ard so that its face is against the graticule. Rotate CRT so
that the trace coincides ith the horizontal graticule line hen properly
positioned ith the VERTICAL POSITION control. Clamp the CRT in position.
Recheck the trace orientation.
c. Apply 0.2 volts from the calibrator to the input connector of the plug-in unit.
With Main S eep TRIGGERING LEVEL and Main S eep STABILITY controls, obtain a
stable trace. This operation gives a preliminary check on the operability of
the triggering circuits.
No observe the display from a position above and in front of the screen.
Position the display to various parts of the screen by means of the position
controls. Observe any aviness on the internal face of the CRT, Any
appreciable aviness is cause for rejection of the CRT.
d. Set HORIZONTAL DISPLAY at DELAYING SWEEP position. Turn Main S eep STABILITY
CCW, Set delaying S eep TIME/CM at 1 millisec; set Delaying S eep TRIGGERING
LEVEL at 0. Connect VERT. SIG. OUT to TRIGGER OR EXT. SWEEP IN. With EXT.
SWEEP ATTEN. s itch at XI and ith SLOPE toggle s itch at +, adjust Delaying
S eep STABILITY for stable s eep. Increase INTENSITY setting if necessary to
vie trace.
August, 1956 FD-535-ii

e. Using the settings of Part d above, set the Main S eep TIME/CM control
at 100 i-i sec and bring the Main S eep STABILITY control CW to check that
a portion of the s eep is brightened (during Main S eep operation).
No remove calibrator signal, leaving a single trace on the screen.
f. Check the oscilloscope for microphonics. This check is done by rapping
on the test bench, or (not too forcibly) on the top of the panel.
Experience ill tell you ho forcibly to rap and ho much vertical
deflection ill occur in a correctly operating instrument as a result of
microphonics. In any case, any definitely oscillatory type of microphonic
display should indicate that a tube should be changed because of vibration
of its elements. The 6CL6 vertical driver tubes, V508 and V0O9, are common
sources of microphonicsj other tubes in the vertical system may also be at
fault. (Belo SN 1059» 6BQ7's ere used).
6. To adjust vertical AMPL GAIN.— Use 117 line volts. Apply 0.2 volts from cali
brator to INPUT of po er-test plug-in unit. Set AMPL GAIN control (on left
side of oscilloscope, to ards the rear) for 2 cm of vertical deflection (peak-
to-peak). (This is a preliminary adjustment only.)
7. To adjust CRT (SQM control.— Use 117 line volts.
a. Apply more vertical signal from the calibrator than is needed to cover the
~ graticule vertically. Position the display vertically so that the flat
tops of the square aves are off the screen both above and belo the grat
icule. Turn up the INTENSITY control so that the spot, moving rapidly in
the vertical direction, makes a visible trace. No set the CUT GEGM adjust
ment (rear of top deck) so that the vertical traces near the ends of the
graticule are as nearly straight and vertical as possible.
In case the CRT is defective, a tilt may be observed in some of these
traces. If the tilt exceeds 1 mm over the 6-cm height of the graticule,
the CRT must be rejected.
b. As a further check on the CRT GEOM adjustment, remove the calibrator sig-
~ nal, and position the single trace first to the uppermost graticule line
and then to the lo est graticule line. The trace should lie along the
upper and the lo er graticule lines ithout noticeable up ard or do n ard
bo ing. A re-touching of the CRT GEOM adjustment should clear up any
normal amount of bo ing.
Observe hether or not a tilt is introduced into the trace at either the
top or the bottom of the graticule. If the tilt in either trace position
exceeds 1 mm over the 10-cm graticule length, the CRT must be rejected.
c. The CRT GEOM adjustment is often rather broad. Within the limits of its
adjustments giving good results under Parts a and b of this step, use that
setting hich gives the least noticeable flare on the screen ( hen the
SWEEP LENGTH control on the top deck of the oscilloscope, and the positioning
controls, are set so that the display lies entirely ithin the graticule.)
August, 1906 FD-535-0

8. To check for compression in the vertical system,— Apply a calibrator signal hich
provides 2 cm of vertical deflection hen the display is centered vertically.
This deflection should not be reduced by more than 0.5 mm hen the display is
raised to the top of the graticule or lo ered to the bottom of the graticule by
means of the VERTICAL POSITION control.
9. To check dc balance of vertical system.—
a. Remove calibrator signal. Short-circuit vertical plates of CRT, and observe
the trace position. With the short-circuit removed, adjust the VERTICAL
POSITION control for the same position of the trace.
b. Short-circuit Pins 2 and 7 of V6o6. Change V606 if the resulting vertical
” shift in trace position exceeds 0.2$ cm. (If at any point in the present
Step 9 it becomes necessary to interchange or replace tubes, redo Parts 5(f),
8 and 9(a).)
c. Short-circuit Pin 2 of V570 to Pin 2 of V580. Interchange or replace these
tubes if the resulting vertical shift in trace position exceeds 1 cm.
d. Short-circuit Pins 2 and 7 of V558, and change V558 if the resulting vertical
shift in trace position exceeds 1 cm.
e. Short-circuit grid of V508 to grid of V509 by operating the push-button s itch
on the panel of the po er-test plug-in unit. Interchange or replace these tubes
if the resulting vertical shift in trace position exceeds 2 cm.
10. To check for vertical shift ith varying line voltage.— The vertical position of
the trace may shift as the po er-line voltage is changed. This shift may be due
to either or both of t o independent causes: (l) a variation in emission
unbalance ith heater temperature of the 6CL6 or 6BQ7 vertical driver tubes, V508
and V509; or (2) a possible re-direction of the electron streams, because of the
magnetic effects of the heater currents, causing a change in the screen-to-plate-
current ratios in V508 and V509. To check for this vertical shift from either
cause:
With the HORIZONTAL DISPLAY s itch at MAIN SWEEP NORMAL, and ith the po er
line voltage at 105 volts,obtain a single trace across the screen. Center
this trace vertically ith the VERTICAL POSITICN control. Raise the line
voltage to 125 volts. If any resulting (fast or slo ) shift in vertical posi
tion of the trace exceeds 0,5 cm, try changing V508 or V509. (if these tubes
must be changed, recheck Steps 5(f), 8, 9(a) and 9(e).)
11. To recheck vertical AMPL GAIN adjustment, and to check the c alibrator attenuator.—
a. Set the AMPL GAIN control so that 0.2 volts from the calibrator produces
"" a vertical deflection of 2 cm.
b. Replace the po er-test plug-in unit ith the 53/5UC plug-in. ^et the input
*" selector at DC. Set the VOLTS/CM control at 0.05 and feed in 100 mv
from the calibrator. Be sure that the red VARIABLE knob on the VOLTS/CM
control is fully CW. A deflection of 2 cm should be obtained. Other
positions of the calibrator attenuator should be checked similarly. The
results should be those tabulated, ithin ±2$:
August, 1956 f d -535-6

Calibrator
VOLTS/CM setting attenuator Vertical
on plug-in unit setting deflection
0.05 100 niv 2 cm
0.05 0.2 volts k "
0.1 0.5 " 5 "
0.2 1 " 5 "
0.5 2 " k "
]_ ^ ti cj 11
2 10 " 5 "
5 20 » U «
10 50 " 5 "
20 100 » 5 "
12, To adjust DC SHIFT COMP control.—
a. After completing the above step, remove the calibrator signal from the
INPUT connector. Leave the INPUT SELECTOR in the DC position. Set the
MODE s itch to "A ONLY" or to "B ONLY." Position the trace at - 3 cm
(that is, 3 cm belo the graticule center line).
b. Connect a 1.5-volt cell (or anohmmeter) bet een GND on the oscilloscope
and the plug-in unit connector. Adjust the VOLTS/CM control on the plug
in unit so that the trace moves to +3 cm. (That is, make the settings
such that t he trace is at -3 cm hen the cell is disconnected, but rises
to +3 cm hen the cell is connected.)
c. Note the position of the trace immediately upon connecting the cell. Leav-
~ ing the cell connected for several seconds, observe hether or not the
trace slo ly drifts 1 or 2 mm up or do n. If it does, adjust DC SHIFT
COMP control so that the drift occuring hen the cell is connected is a
minimum.
(NOTE: This step calls for connecting and disconnecting the cell sev
eral times, at intervals of several seconds, and observing that the
trace comes at once to almost its final position, each time the cell is
connected. )
13. To set TRIGGERING LEVEL controls to physical center.— (For this adjustment,
the TRIGGERING MODE control should NOT be set to AC AUTO.)
a. Connect a voltmeter from the junction of Rl6 and Rl? to chassis. (Rl6
is connected to the center arm of the Main S eep TRIGGERING LEVEL con
trol, hich is the control nearest the panel in the dual-control assem
bly of hich it is a part.) Set the Main S eep TRIGGERING LEVEL control
so that zero deflection is obtained even on the 3-volt range of the
voltmeter.
b. Loosen the Main S eep TRIGGERING LEVEL knob on its shaft. Turn the knob
on its shaft so that its index points to "0" on the panel, and tighten
the knob on the shaft. Recheck that a voltmeter reading of zero is ob
tained hen the knob index is at "0". Remove the voltmeter connections.
August, 1956 f d -535-7

c. No move the voltmeter ungrounded connection to the junction of R107 and
R108. (R107 is connected to center arm of Delaying S eep TRIGGERING
LEVEL control.) Set the Delaying S eep TRIGGERING LEVEL control so that
zero deflection is obtained even on the 3-volt range of the meter.
d. Loosen the Delaying S eep TRIGGERING LEVEL knob on its shaft. Turn the
knob on its shaft so that its index points to "0" on the panel, and tighten
the knob. Recheck that a voltmeter reading of zero is obtained hen the
knob index is at "0".
111. To adjust TRIGGERING LEVEL CENTERING.— Settings:
Main S eep TRIGGERING LEVEL— 0. TIME/CM— 1 millisec.
TRIGGER SLOPE— +BJT. 5X MAGNIFIER— OFF.
TRIGGERING MODE— AC SLOW. HORIZONTAL DISPLAY— MAIN SWEEP NORMAL.
a. Display calibrator signal. Set calibrator output and the VOLTS/CM s itch
for 3 or 4 mm of vertical deflection. Set Main S eep STABILITY control and
the TRIGGERING LEVEL CENTERING control so that a stable display is obtained.
Then make further adjustments of TRIGGERING LEVEL CENTERING so that the s eep
triggers equally ell on +INT and -INT settings of the TRIGGER SLOPE s itch.
Note: The Main S eep STABILITY control and the Main S eep TRIGGERING LEVEL
control may be touched up slightly to obtain the above result. The final
setting of the Main S eep STABILITY control ill be in the vicinity of that
needed just to produce triggering. The final setting of the Main S eep TRIG-
GERING LEVEL control ill be essentially at "0". After the TRIGGERING LEVEL
CENTERING is adjusted, reliable triggering must be obtained as the TRIGGER
SLOPE s itch is moved back and forth bet een the +INT and the -INT positions
ithout touching the Main S eep TRIGGERING LEVEL or Main S eep STABILITY
controls.
The above is a preliminary adjustment of the TRIGGERING LEVEL CENTERING con
trol. The final adjustment is described under Step 15, belo .
b. Check the polarity of the TRIGGER SLOPE s itch on +INT and -INT positions.
The leading edge at the left end of the graticule should be a rising edge
hen the s itch is in the +INT position, and it should be a falling edge
hen the s itch is in the -INT position.
15. To adjust TRIGGER SENSITIVITY control.— Settings of the oscilloscope being cali
brated:
Main S eep TRIGGERING LEVEL— 0.
Main S eep STABILITY— CCW.
TRIGGER SLOPE— +LINE.
TRIGGERING MODE— AC SLOW.
HORIZ. DISPLAY— MAIN SWEEP NORMAL
TIME/CM— 100 usee.
5X MAGNIFIER— OFF.
MULTIPLIER— XI.
INTENSITY— CCW.
Settings of test oscilloscope:
TRIGGER SLOPE— +LINE. TIME/CM— 1 millisec.
August, 1956 FD-535-8

TRIGGERING MODE— AC SLOW.
HORIZ. DISPLAY— INTERNAL SWEEP 5X MAGNIFIER— ON
VOLTS/CM-^27~
Connect 2X probe of test oscilloscope to Pin 1 of V20 (or to lead from that
pin to the TRIGGERING MODE s itch). With TRIGGER SENSITIVITY turned CW,
the aveform of Fig. 1 should be seen on the test oscilloscope, (Figure
may be inverted. If so, s itch to -LINE triggering on test oscilloscope.)
A
The TRIGGER SENSITIVITY control should no be gradually turned CCW until
the self-oscillation indicated at A just dies out. The result is a dis
play sho n in the solid line of Fig. 2, The TRIGGER SENSITIVITY control
should be turned further in the CCW direction until the peak B drops to a
point C (dotted line, Fig. 2) hich has a height above D equal to one-
half its original height. —
After this adjustment, repeat Step lli(a), but this time obtain reliable
triggering on signals hich produce a vertical deflection of not more than
a trace idth.
Check that reliable triggering ith a vertical deflection of not much more
than a trace idth occurs hen the TRIGGERING MODE s itch is set to AC FAST,
and hen the TRIGGER SLOPE s itch is alternated bet een +INT and -INT as
above.
16. To set INT TRIG DC LEVEL.— Display calibrator aveform at about 2 or 3 mm
vertical deflection. KEEP THE DISPLAY CENTERED VERTICALLY about the grati
cule horizontal center line. Use these settings:
Main S eep TRIGGERING LEVEL— 0. TRIGGERING MODE— DC.
TRIGGER SLOPE— +INT. TIME/CM— 1 mflTisec.
5X MAGNIFIER— OFF. MULTIPLIER— XI
HORIZONTAL DISPLAY— MAIN SWEEP NORMAL.
Adjust the Main S eep STABILITY control and the INT TRIG DC LEVEL con'
trol for a stable trace. With correct a djustment of the INT TRIG DC
LEVEL, the s eep ill trigger equally ell on +INT and on -INT.slope
settings, ith a given setting of the Main S eep STABILITY control.
17. To check AC AUTO operation.— Settings:
Main S eep TRIGGERING LEVEL— CW.
Main S eep STABILITY— CCW.
TRIGGER SLOPE— +INT.
TRIGGERING MODE— AC AUTO.
Use no signal input. Operation in the
TIME/CM— 100 jisec.
MULTIPLIER— XI
5X MAGNIFIER— OFF.
HORIZ. DISPLAY— MAIN SWEEP NORMAL
AC AUTO mode is indicated if, upon
August, 1956 FD-535-9

advancing the Main S eep STABILITY control slo ly CW, you obtain a trace, and
if further advance of this c ontrol results abruptly in a brightening of the
trace. (The first trace results from triggering of the s eep by the trigger-
shaper multivibrator operating in a free-running manner at about 50 cps. The
brightening occurs hen the s eep-generating circuits themselves become free-
running at advanced Main S eep STABILITY settings.
No apply sufficient calibrator signal to provide 2mm of vertical deflection.
Set the TIME/CM control to 1 millisec. A stable display should be obtained
hen the Main S eep STABILITY control is set for triggered operation of the
s eep. A further check on the AC AUTO mode is obtained by removing the input
lead at the calibrator connector. Usually sufficient 60-cps signal ill be
picked up in the room so that if the bare end of the lead is held in the hand,
a (distorted) ac ave can be obtained on the screen. The TIME/CM and VOLTS/CM
controls should be s et to obtain a display of suitable size on the screen, and
it should be checked that a stable display can be obtained by setting the Main
S eep STABILITY control if necessary,
18. To adjust EXT SWP AMPL DC BAL.— Ground EXTERNAL SWEEP IN. Set:
HORIZONTAL DISPLAY--EXT SWP. EXT. SWEEP ATTEN. (knob)— CW.
5X MAGNIFIER— ON." ATTEN. (toggle;— XI.
Main S eep STABILITY— CCW.
Position the s pot on the screen by means of the HORIZONTAL POSITION control.
Adjust EXT SWP AMPL DC BAL control so that the spot remains stationary on the
screen as the EXTERNAL SWEEP ATTENUATOR knob is turned back and forth through
out its range.
19. To set C2k0 and C25I+.— Settings:
Main S eep TRIGGERING LEVEL— 0.
TRIGGER SLOPE— +EXT.
TRIGGERING MODE— AC SLOW.
HORIZONTAL DISPLAY— EXT. SWEEP.
SLOPE (toggle)— +
VOLTS/CM— 10.
5X MAGNIFIER— ON .
ATTEN. (toggle) — XI.
EXT. SWP. ATTEN.— CW.
TIME/CM— 1 millisec.
"MULTIPLIER— XI.
CALIBRATOR— 0.5 volts.
a. Connect 1-kc output from Type 105 to TRIGGER OR EXT. SWEEP IN. Have the
Type 105 terminated at its output connector ith a 52-ohm terminating resis
tor. Use a 52-ohm cable, terminated at the oscilloscope end in a 5*1 (lli-db)
52-ohm L pad. Connect the Sync Output of the Type 105 to TRIGGER INPUT.
Connect SAWTOOTH MAIN SWEEP to input of plug-in preamplifier. Adjust
STABILITY for a stable square- ave display hich is presented vertically,
rather than horizontally, across the screen. Set the Output Amplitude con
trol of the Type 105 for about 2 cm of horizontal deflection. Adjust C2i|0
(at right rear of top deck) for best square- ave r eproduction.
b. Next, turn the 5X MAGNIFIER off, and increase the Output Amplitude setting of
— the Type 105 so that a horizontal deflection of about 2 cm is again obtained.
Adjust C251i (near C2U0) for best square ave reproduction.
August, 1956 f d -535-i o

Any horizontal instability observed in the display during this step should
lead to a check of V113, V120 and V130 and their associated circuits for
hum or noise.
20. To check SLOPE s itch for correct polarity.— Using the same settings as for
Step 19, check that ( + ) position of SLOPE toggle s itch provides display at
the right-hand side of the screen, hile the (-) position of the s itch
moves the display to the left-hand side.
21. To adjust C110, C101 and C100. This operation is performed to adjust the
horizontal-amplifier input capacitance to the standardized values.
a. Use the same settings as for Step 19, ith 5X MAGNIFIER on. The connection
from the Type 105 to the TRIGGER OR EXT. SWEEP IN connector is no to be
made through a Input Capacitance Standardizer (I4X Atten.) (Stock
No. 011-021) in place of the L pad used in Steps 19 and 20. Set the
Type 105 Output Amplitude control for about 2 cm of horizontal deflection.
With the fingers, adjust C110 (behind ATTEN. toggle s itch) for best
square- ave leproduction, mean hile holding the handle of the SLOPE toggle
s itch ith the other hand. (This adjustment ill no longer be correct
hen the fingers are r emoved from C110; cabinet capacitance ill later
restore the aveform.) Operate the SLOPE toggle s itch up and do n
rather fast during the adjustment of C110 to get a display hich "alter
nates" to right and left sides of screen; this permits a better appraisal
of the square ave. Consider only that portion of the aves extending
vertically along the middle of the "alternating" display.
b. S itch the A T T M . toggle s itch to X10. Repeat Part a of this step, but
this time adjust ith the fingers C100 ( hich affects the "slope" of the
square ave) and C101 ( hich affects the "spike"). C100 and C101 inter
act.
c. If the vertical center part of the display shifts to left or right hen
the SLOPE toggle s itch is operated, suspect a gassy condition in V113
(12AU7),and change this tube.
22. To adjust delay line and to set vertical amplifier coils.—
a. Insert special "high-frequency" plug-in unit, identified by its plastic
chassis.*
b. Check that the gray signal leads from Pins 1 and 3 of the preamplifier
plug are clear of each other and clear of other ires. Similarly for
the gray signal leads to the delay-line input coils. Use spudger, if
necessary, to dress the cabled po er leads back under the preamplifier
plug and a ay from the gray signal conductors.
c. Make sure that R570 and R580 (in vertical output amplifier), and leads to
” CRT vertical plates, are ell a ay from each other and fran other objects.
*There is a possibility, as these instructions are being prepared, that the 53/51lK
plug-in unit may later be specified for this step, rather than the special high-
frequency plug-in unit mentioned above.
August, 1956 FD-535-11

d. Preset L370 and L380 (in vertical output amplifier) so that the slugs pro
ject about 3/l6" belo the lo est turns of the coils, as seen hen the light
source is placed on the opposite side of the translucent coil form from the
vie er.
e. Preset the delay-line input coils so that the slugs are five turns in from
” their outermost position.
f. Settings:
Main S eep TRIGGERING LEVEL— 0, HORIZONTAL DISPLAY— M I N SWEEP NORML
Main S eep TRIGGER SLOPE— ±INT. 5X MGNIFIER— OFF.
g. Feed a 300-kc to f?00-kc square- ave output of Type 10$ to input of plug-in
unit. Have the Type 103 terminated at its output connector in a 32-ohm
terminating resistor, and use a 32-ohm cable to the oscilloscope plug-in unit.
Use a 3:1 (lU-db) 32-ohm L pad at the oscilloscope end of the cable. Set
the Type 103 Output Amplitude control for about i| cm of vertical deflection.
h. The delay line affects only the first half microsecond of the square ave.
"" Delay-line "trimmer" capacitors at the bottom of the oscilloscope affect the
early part of the ave; upper capacitors affect later parts of the ave.
The portion of the ave affected by a particular capacitor can be identified
by the do n ard bump occurring hen that capacitor is touched ith the metal
bit of a scre driver.
CAUTION
The capacitors have +200 volts on them. Do not touch them ith the
fingers.
Adjust the capacitors of the delay line so that " rinkles" of magnitude greater
than the trace idth are absent, and so that the "level" of the trace is con
stant across the top of the square ave. Avoid use of the first positive ave
triggered on + slope. (This may have a slight curvature in these instruments.)
Neglect irregularities appearing on the bottoms of the square aves— adjust
only for flat tops or positive portions of the aves.
Suggestions:
Make only small changes in the capacitor adjustments. Typically,
any one adjustment should be not more than that needed to raise or
lo er the corresponding portion of the display by an amount equal
to a trace idth.
Work al ays for maximum smoothness in the horizontal part of the
display. Do not expect that a single adjustment of a capacitor
ill get the correct display height at any given point. Rather,
ork back and forth over a range of five or six capacitors at a
time, making very small adjustments of the capacitors, and striving
al ays to make the display smooth and free from sharp comers.
After each fe adjustments, set the TIME/CM and MULTIPLIER s itches
August, 1936 FD-333-12

to slo er s eep positions, so that the tops of the square aves
line up closely together. This ill sho the effect (of the
adjustments you have just made) upon the general "level" of the
square- ave tops. It must be kept in mind that the finished
delay line must transmit square aves hose tops appear con
sistently level, even hen you use s eeps so slo that each ave
top appears only about a millimeter in length.
A small residual rinkle called a "termination bump" may sometimes re
main at about the mid-point of the square ave. This should be adjusted
for the least-noticeable value by setting the last (upper) one or t o
capacitors of the delay line hen the s eep is set for about 1 usec/cm.
If the termination bump is excessive, the values of the line-terminating
resistors R938 and R9I4O (775& each), and of the terminating capacitors
C938 and C9U0 (lpj-tf each), should be checked.
i. After, and only after, the rinkles have been eliminated and the general
level of the square ave has been made satisfactory, try small increases
in Lf>70 and L580. Make equal small changes in these inductances. These
changes have the effect of raising the level of the early portion of the
ave. The level may be restored to normal by readjusting the first trim
mer capacitors. The over-all result is a "squaring up" of the leading
edge of the ave. This process is to be continued, a half-turn or a
turn of each coil at a time, as far as practicable from the vie point of
obtaining a good square- ave response.
j_. The delay-line input coils should no be readjusted for increased in
ductance. These affect the leading edge only. Make equal small increases
in both inductances. Then make any needed compensating adjustments of the
first trimmer capacitors. Continue this process as far as practicable from
the vie point of obtaining a good square- ave response.
Note: If the early part of the square ave persistently demonstrates over-
shoot, or if there is "ringing" (damped oscillation), then:
See that you do not have excessive inductance in the amplifier com
pensating coils L5>70 and L560, or in the input coils to the delay
line.
See that fixed vertical-amplifier coils L557 and L560 (1.2 |ih)
and L63U and L635 (8.8|ih) are correct. (For example, it ould be
easy to get some of these coils interchanged during assembly.)
Check the values of R631; and R635 (820 ohms) in the vertical-plate
leads to the CRT, (If these resistors a re lo , overshoot may re
sult. If they are high, it may be impossible to get the band idth
required under Step 23, belo .)
23. To check band idth of vertical system.— After completing the above step, feed
into the plug-in unit connection a frequency in the lo est-frequency band of
the Type 190. A 52-ohm terminating resistor should be inserted bet een the out
put cable attenuator of the Type 190 and the input connector of the oscilloscope.
August, 1956 f d -535-13

With the TIME/CM control at 100 nsec, set the vertical deflection exactly upon
some hole number of centimeters— say 3 cm or h cm. Without disturbing the
other settings, increase the output frequency of the Type 190 untilthe deflection
decreases to a value hich is 70$ of the original deflection. The frequency
hich gives this deflection is the 3-db-do n frequency of the oscilloscope ver
tical system. Typical values obtained range from 12.1 me to 12.3 me. If the
band idth is insufficient, recheck items 22b, 22c, 22i, and 22^.
2i|, To check HF SYNC operation.— Supply a 30-mc signal from the Type 190, ith amp
litude sufficient to produce 5 mm of deflection. Use these settings:
A setting of the Main S eep STABILITY control should be found at hich the 30-mc
sine- ave display is stable.
2$. To adjust SWP CAL.— Insert a Dual Trace Preamplifier (530 or 53/5UC plug-in unit
may be used). Settings:
HORIZONTAL DISPLAY— DELAYING SWEEP. Delaying S eep TIME/CM— 1 millisec.
SLOPE (toggle)— +. LENGTH— CW.
5X MAGNIFIER— OFF .
Connect a jumper from VERT.SIG. OUT to TRIGGER OR EXT. SWEEP IN. Display
1-millisec markers from Type 180, and adjust belaying S eep STABILITY and De
laying S eep TRIGGERING LEVEL for stable display. Keeping the second marker
precisely beneath the 1-cm graticule line ith the HORIZCNTAL POSITION control,
adjust the SWP CAL control so that the tenth marker falls precisely under the
9-cm graticule line.
26. To set the Delaying S eep LENGTH.— Set the Delaying S eep to free-run at 1 mil-
lisec/cm. Connect the middle (black) ire of the "resistance selector" to the
upper end of the 12-K resistor, R182, in the Delaying S eep chassis. Connect
the right-hand (red) ire to the lo er end of R182. Connect the left-hand (red)
ire to the upper end of R180 (15-k). Set the knobs of the "resistance selector"
to values that make the shortest s eep obtainable ith the LMGTH control lie
bet een 3.2 and 3.8 cm, hile making the longest s eep obtainable ith the
LENGTH control lie bet een 10.3 and 10.8 cm. Remove the "resistance selector"
cables from the Type 535. Connect a ig- att carbon resistor (R181-B) having the
value sho n on the left dial of the "resistance selector" bet een the upper ends
of R182 and R180. Connect a J- att carbon resistor (R182-B) having the value
sho n on the right dial of the "resistance selector" across R182. Recheck the
range of s eep lengths obtainable by operation of the LMGTH control.
27. To time main s eep to delaying s eep.— Settings:
H0RIZ. POSITION— MAIN SWEEP NORMAL.
Main S eep TRIGGERING LE7EL--0.
TRIGGERING SLOPE— +INT.
TRIGGERING MODE— HF SYNC.
TIME/CM— 0.1 psec.
MULTIPLIER— XI.
5x MAGNIFIER— ON.
Delaying S eep STABILITY— CCW.
HORIZONTAL DISPLAY— MAIN SWEEP NORMAL
TRIGGER SLOPE— +INT.
TRIGGERING MODE— AC SLOW.
5X MAGNIFIER— OFF.
TfMfe/CM— 1 millisec.
MULTIPLIER— XI.
August, 1956 FD-535-1L

Display 1-millisec markers f rom Type 180, and adjust Main S eep STABILITY
and Main S eep TRIGGERING LEVEL controls for stable display. Keeping the
second marker precisely beneath the 1-cm graticule line ith the HORIZON
TAL POSITION control, adjust R99M (on Main S eep TIHE/CM s itch bracket)
so that the tenth marker falls precisely under the 9-cm graticule line.
28. To adjust main SWP LENGTH.— With the same settings as those used in Step
27, adjust SWP LENGTH control for s eep of 10§- cm.
29. To adjust M G GAIN.—
a. With the same settings as those used in the step just completed, feed
in 1-millisec and 100-psec markers from Type 180. Adjust Main S eep
STABILITY and Main S eep TRIGGERING LEVEL controls for a stable display,
b. No turn gX MAGNIFIER on. With the HORIZONTAL POSITION control, set
"" the sixth 1-millisec marker approximately under t he vertical center
line of the graticule.
c. Adjust MAG G AM and HORIZONTAL POSITION so that 100-psec markers fall
precisely under the 1-cm and the 9-cm graticule lines, ith t o mark
ers for each cm of distance bet een these lines. At graticule lines
ithin the middle 8 cm, the markers should align ith the graticule
lines ithin a tolerance of ±1 mm.
30. To adjust SWP/MAG REGIS.— After completing the above s tep, position the
first marker beneath the graticule center line by means of the HORIZONTAL
POSITION control. Then turn the gX MAGNIFIER off, and by means of the
SWP/MAG REGIS control, reposition the first marker beneath the center line.
31. To check the main s eep timing, g-sec/cm to lOO-psec/cm ranges.— After com-
pleting the step above, turn the gX MAGNIFIER off. Then
a. S itch the TIME/CM control to 100 psec. Position the second marker pre
cisely under the 1-cm graticule line by means of the HORIZONTAL POSITION
control. Check that the markers coincide ith the graticule lines ith
in ±1$, over the middle 8 cm of the graticule length.
b. Reset the TIME/CM s itch to 1 millisec. Turn off the 100-psec markers
~ on the Type 180, and make any neededreadjustment of the TRIGGERING
LEVEL to obtain a stable display of the 1-millisec markers. Set the
MULTIPLIER to X2. Position the third 1-millisec marker precisely under
the 1-cm graticule line ith the HORIZONTAL POSITION control. Check the
timing over the middle 8 cm of the graticule length. (T o markers should
be obtained for each cm of graticule length.) Tolerance, ±l°o.
c. Repeat Part b of this step, this time using only g-millisec markers.
Have the TIME/CM s itch in the 1-millisec position, and the MULTIPLIER
in the Xg position. With the second marker positioned under the 1-cm
graticule line, you should obtain 1 marker/cm ithin a tolerance of
±1$, over the middle 8 cm of the graticule length.
d. No apply only 1-millisec markers. 'With the TIME/CM s itch in the 1-millisec
August, 19g6 FD-g3g-lg

position and ith the MULTIPLIER in the 2,5-1 position, check that the red
variable multiplier knob provides control of the number of markers per cm
over at least the range from 2,5 to 1,
e. With the MULTIPLIER in the 5-2 position, check that the red variable multi-
"" plier knob provides control of the number of markers per cm over at least
the range from 5 to 2,
f. Turn the black MULTIPLIER knob to the 12-5 position, and set the red variable
multiplier knob CW. S itch to a TIME/CM position of 100 psec. Six markers
should appear, approximately filling the graticule space horizontally. At
least 13 markers should appear in the same horizontal space hen the red
variable multiplier knob is turned CCW.
g. Set TIME/CM at 10 millisec and MULTIPLIER at XI. Feed in 10-millisec markers
only from Type 180. With the second marker positioned under the 1-cm grati
cule line, check that the timing (1 marker/cm) is ithin a ±1/ tolerance over
the middle 8 cm of the graticule.
h. Repeat Part g of this step, this time using 100-millisec markers and a
TIME/CH setting of 100 millisec. Tolerance, ±1$.
i. Inserting 1-sec markers, and using a TIME/CM setting of 1 sec, check the
timing of the s eep ith MULTIPLIER settings of XI, X2 and X5. Tolerance,
±1%, (On XI position, one marker/cm should be observed. On X2, t o mark-
ers/cm should be observed. On X5, five markers/cm should be observed.)
32. To set timing of main s eep, 10-psec/cm to 0.1-psec/cm ranges.—
a. Preset 0278 and C286 to mid-range positions.
b. With TIME/CM s itch at 10 usee and ith MULTIPLIER at XI, display 10-psec
markers. With the HORIZONTALPOSITION control, keep the second marker pre
cisely under the 1-cm graticule line. Adjust C99F (on TIME/CM s itch) so
that the 10th marker lies precisely under the 9-cm graticule line. Correct
timing (1 marker/cm) should be obtained ithin the middle 8 cm of graticule
length, ithin a tolerance of ±1^.
c. Repeat Part b of this step. This time, display 1-psec markers ith a TIME/CM
~ setting of 1 psec. In this part, adjust C99H (on TIME/CM s itch).
d. Set TIME/CM at 0.1 jusec and MULTIrLIER at X5. Insert 1-psec markers. Posi
tion the first marker off the screen to the left, ith the HORIZONTAL POSITION
control, and position the second marker under the 1-cm graticule line. Main
taining this position of the second marker precisely im-th the HORIZONTAL POSI
TION control, adjust C99J (on TIME/CM s itch) so that the sixth marker lies
precisely under the 9-cm graticule line. Correct timing (t o cm bet een markers)
should be obtained ithin the middle 8 cm of graticule length, ithin a tol
erance Of ±l/o.
e. Set TIME/CM at 0.1 psec and MULTIPLIER at XI. Display 10-mc sine aves from
the Type 180. Touch up C25U and adjust C267 (the latter is mounted near the
August, 1956 f d -535-16

MAG. GAD? control) for best linearity and timing of the display, ob
taining one cycle of the sine ave for each cm of graticule length, over
the middle 8 cm of graticule length. Settings of C2$h and C267 interact;
C25it serves principally to set the s eep speed, hile C267 serves princi
pally as a linearity adjustment.
f. Recheck: Part c of this step. Then, displaying 1-nsec markers ith a
"" TIME/CM setting of liasec/cm, check the timing ith the MULTIPLIER on the
X2 position. Over the middle 8 cm of the graticule, you should observe
2 markers/cm, ithin a tolerance of ±1$. (Note? If C2lt0 or C2$h are
very far out of adjustment, you may get an effect hich could lead you to
believe that the multiplier resistors are out of tolerance. C2$h has
been retouched in Part e of this step, above. If the present check on
the MULTIPLIER X2 position seems out of tolerance, you may ish to re
check the adjustment of C2lj0, as given in Step 19, before trying ne multi
plier resistors.)
g. Displaying 5-M-sec markers ith a TIME/CM setting of 1 (xsec/cm, check the
timing ith the MULTIPLIER on X$ position. Over the middle 8 cm of the
graticule, you should observe 1 marker/cm, ithin a tolerance of ±1$,
(The note attached to ^art f of this step, above, also applies here.)
h. Recheck Parts d and e of this step, until no further adjustments under these
steps are required.
33. To adjust 0278 and C286.— Settings:
Main S eep TRIGGERING LEVEL— 0.
Main S eep TRIGGER SLOPE— +INT.
TRIGGERING MODE— AC SLOW
HORIZONTAL DISPLAY— MAIN SWEEP NORMAL.
Connect 1-psec marker output of Type 180 to INPUT of plug-in unit. Cap-
acitively couple the 30-mc output of the Type 180 to one of the vertical
plates of the CRT. (The value of the coupling capacitor is not at all
critical. A suggested value is 20 [ipf.) Set the Main S eep STABILITY
control for a stable display of the 50-mc sine aveT Make these adjustments:
a. Set the HORIZONTAL POSITION control at about the position of 1100 hours
(slightly CGI from mid-scale). Set the VEFNIER at mid-scale. Adjust
C278 and C286 (keeping them approximately balanced ith respect to each
other) for best timing and linearity of the display. There should be
precisely eight cycles of the sine- ave display over the middle 8 cm of
the graticule length. Within the middle 8 cm of the graticule, there
should be one cycle of the sine ave for each centimeter of the grati
cule length.
b. Turn the HORIZONTAL POSITION and VERNIER knobs CCW. If these settings
"" bring into vie the last fe cycles of the display, hich are obviously
nonlinear, then reset the VERNIER knob to ards CW until these nonlinear
portions are positioned off the right end of the graticule. There should
no be eight cycles of the sine- ave display over the middle 8 cm of the
graticule length. Within the middle 8 cm of the graticule, there should
be one cycle of the sine ave for each centimeter of graticule length,
ithin a tolerance of ±2%,
Main S eep TIME/CM— 0.1 nsec.
MULTIPLIER— XI.
5X MAGNIFIER— ON.
August, 1956 FD-53S-17

c• Turn the HORIZCNTALPOSITION knob CW until the left end of the display be
comes visible. No turn the knob a short ay CCW until the first fe cycles,
hich are obviously nonlinear, are positioned off the left end of the screen.
Check the trace for eight cycles of the sine ave over the middle 8 cm of the
graticule length. Within the middle 8 cm, there should be one cycle of the
sine ave for each centimeter of graticule length, ithin a tolerance of
±256.
Note: If it is not possible to obtain the results described for this opera
tion, and if parts and tubes in the s eep and s eep-amplifier cir
cuits are good and are properly connected, then the fault probably
lies in the ay in hich Steps 19 and 32 ere carried out, so that
it is ise in case of difficulty to recheck these steps.
To check the horizontal gain.— Settings:
HORIZONTAL DISPLAY— EXT. SWEEP. SLOPE (toggle)— +.
EXT. SWEEP ATTEN.— CW, ATTEN. (toggle)— XI.
5X MAGNIFIER— ON.
Feed 0.2 volt from the calibrator.to TRIGGER OR EXT. SWEEP PI. Position the
s eep on the screen ith the HORIZONTAL POSITION control. Length of s eep
should be not less than 1 cm.
No increase the calibrator output to 2 volts. Adjust EXT. SWEEP ATTEN. knob
for a horizontal deflection of 10 cm. Thro the ATTEN. toggle s itch to the
X10 position, and turn the calibrator output to 20 volts. The ne horizontal
deflection should be 10 cm +1 minor division. This procedure checks the cor
rectness of the attenuation ratio of the X10 fixed attenuator.
35. To set DELAY START ADJ and DELAY STOP ADJ. — Settings:
Main S eep TRIGGERING LEVEL— CW or CCW.
Main S eep STABILITY— CW.
TRIGGER SLOPE— +INT .
Main S eep TIME/CM— 10 p-sec.
MULTIPLIER— XI.
HORIZONTAL DISPLAY— DELAYING SWEEP.
gX MAGNIFIER— OFF.
Delaying S eep TIME/CM— gOO psec.
LENGTH— CW.
SLOPE (toggle)— +.
ATTEN. (toggle)— XI.
a. Advance Delaying S eep STABILITY to obtain trace. Adjust INTENSITY for
" moderate brightness. Observe that a short brightened region (due to Main
S eep unblanking) appears on trace. The brightened portion should move
along the trace hen the DELAY-TIME MULTIPLIER is turned.
b. Connect VERT. SIG. OUT to TRIGGER OR EXT SWEEP IN. Display gOO-nsec
— markers from Type !80. Adjust Delaying S eep STABILITY and TRIGGERING
LEVEL for stable display. Align display ith graticule, using HORIZONTAL
POSITION control.
c. Check the registration of the DELAY-TIME MULTIPLIER dial. Dial should
” read 0,0 hen the knob is rotated CCW until stop is reached.
August, 1956 FD-g35-l8

d. Set DELAY-TIME MULTIPLIER 1.0. With DELAY START ADJ., make the
left end of the brightened portion of the trace coincide ith the
1-cm marker. (The left end of the brightened section of the trace
indicates the start of the main s eep.) Then, set the DELAY-TIME
MULTIPLIER at 9.0. With DELAY STOP ADJ., make the left end of the
brightened portion of the trace coincide ith the 9-cm marker.
These adjustments result in preliminary adjustments of DELAY START
ADJ. and of DELAY STOP ADJ.
e. At this point, check the delay-pickoff system for jitter. To do this,
set the Delaying S eep TIME/CM control to 1 millisec, and the Main
S eep TIME/CM control to 1 nsec. Display 500-psec markers ith the
HORIZONTAL DISPLAY control at DELAYING SWEEP. Set the DELAY-TIME
MULTIPLIER so that the brightened portion of the s eep approximately
coincides ith the marker hich appears at the 2-cm graticule line.
S itch the HORIZONTAL DISPLAY control to MAIN SWEEP DELAYED, and
make any slight readjustment of the DELAY-TIME MULTIPLIER needed to
place the magnified marker on the screen. Horizontal jitter in the
marker position should not exceed 2 mm. (Neglect slo drift in marker
position.)
No turn the HORIZONTAL DISPLAY control back to DELAYING SWEEP, and
set the DELAY-TIME MULTIPLIER so that the start of the brightened
portion of the trace approximately coincides ith the marker hich
appears at the 9-cm graticule line. S itch the HORIZONTAL DISPLAY
control to M A M SWEEP DELAYED, and make any slight readjustment of the
DELAY-TIME MULTIPLIER required to place the magnified marker on the
screen. Horizontal jitter in the marker position should not exceed
5 mm, (Neglect slo drift of marker position.)
If the jitter in either of the above tests exceeds specifications, you
can try changing V180 (12AL5), hich may be hummy, noisy or photosensi
tive, You can also try changing V190 (12AU6) or V195 (6U8). A poorly-
grounded socket or an improperly-placed ground connection, particularly
in the region of V195> or V216, can also result in jitter.
No reset the Delaying S eep TIME/CM control to 5>00 psec and the Main
S eep TIME/CM control to 10 psec.
f. Preliminary settings of DELAY START ADJ. and of DELAY STOP ADJ. ere
obtained in Part d of this step. These controls must no be brought
into final adjustment. The adjustments of DELAY START ADJ. and of
DELAY STOP ADJ. interact. These adjustments should be repeated so
that the final adjustments are as nearly accurate as possible at
both the 1-cm marker and at the 9-cm marker.
(Some orkers prefer, after getting a close initial adjustment as above,
to make final adjustments ith the HORIZONTAL DISPLAY s itch in the
MAIN SWEEP DELAYED position. Here, the coincidence of the marker ith
the start of the main s eep is seen directly.)
Adjustment of the DELAY START ADJ. control produces approximately equal
effects at the 1-cm and at the 9-cm positions. Adjustment of the DELAY
August, 1936 FD-535-19

STOP ADJ. control produces about one-tenth the effect at the 1-cm position
as at the 9-cm position. Various "tricks,” based on these relationships,
have been devised to get a quick initial adjustment of DELAY START ADJ.
and DELAY STOP ADJ. One of these tricks is as follo s:
Observe the error ( hich e shall call Eq) at the 9-cm point. The error
is indicated by the number of minor divisions by hich it is necessary to
displace the DELAY-TIME MULTIPLIER from its 9.0-cm reading in order to
make the start of the brightening coincide ith the 9-cm marker. (A posi
tive error is one hich puts the brightening too far to the r ight of the
marker.) Next, observe the error at the 1-cm point. Call this error E-^.
With the DELAY START ADJ., correct the 1-cm error by an amount
l O E ^ — Ecj
Ci B ---- - ----- minor divisions.
(If Ct is positive, move the brightened section to the left.) Then, ith
the DELAY-TIME MULTIPLIER at 9.0, set the DELAY STOP ADJ. so that the left
end of the brightening coincides ith the 9-cm marker. No make any neces
sary final adjustments of the DELAY START ADJ. at the 1-cm point, and of the
DELAY STOP ADJ. at the 9-cm point.
36. To check the Delaying S eep linearity on the 500-|-*sec/cm range.— After completing
Step 35, check that the left end of the trace brightening coincides ith the 2-cm
marker, the 3-cm marker, etc., hen the DELAY-TIME MULTIPLIER is set at the 2.0,
the 3.0, etc., positions, for each major graticule line ithin the middle 8 cm
of graticule length. Maximum permissible error in this indication is 2 minor
divisions on the DELAY-TIME MULTIPLIER.
37. To check DELAY-TIME MULTIPLIER indications on ranges from 10 millisec/cm to
200-M.sec/cm.— After completing Step 36, display 100-tJ.sec/cm markers f rom the
Type 180, using the 200-p.sec/cm position on the Delaying S eep TIME/CM control.
Observe the displacement in minor divisions of the DELAY-TIME MULTIPLIER dial
from the 1.0 position required to make the left end of the brightened portion
of the trace coincide ith the 1-cm marker. Next, observe the corresponding
displacement at the 9-cm position. The difference bet een the displacements
must not be more than 5 minor divisions.
Carry out this process on all ranges from 10 millisec/cm to 200 |isec/cm. On
each range, use an appropriate marker rate from Type 180. The 500 p.sec/cm range
does not have to be rechecked; it has already been adjusted by means of the
DELAY START ADJ. and DELAY STOP ADJ. On no range is the difference bet een the
displacements to be greater than 5 minor divisions.
(In each operation in this step, use settings of the Main S eep TIME/CM and
MULTIPLIER hich ill make the length of the brightened legion satisfactory to
the person doing the calibration. Also, in each operation, use a marker period
selection on the Type 535 hich is suitable for the range being checked on the
Type 535 Delaying S eep TIME/CM s itch.)
August, 1956 FD-535-20