Model 166D, MX-2962/USM-l05A Section VI
Paragraph 6-5
R I6 R67 R63 g. LOW FREQUENCY ADJUSTMENT.
TR SYM 9CM DELAY ICM DELAY Complete step f before performing low frequency
adjustment.
/ (1) Set oscilloscope SWEEP TIME to 10 micro-
seconds/cm and SWEEP MODE to PRESET. Set
Model 166D controls as follows:
SWEEP TIME. ........ 1 millisecond/cm
SWEEP MODE ............. PRESET
TRIGGER LEVEL. ............... +
R-3 TRIGGER SOURCE.. ............ INT
R60 SWP SWEEP SELECTOR . .MAIN SWEEP DELAYED
PRES NTH
DELAY FUNCTION . .TRIGGER MAIN SWEEP
i
1 (2) Set Time Mark Generator for 1 ms markers and
connect to oscilloscope vertical INPUT. Set DELAY
LENGTH to 1 cm. Adjust 1 cm Delay R63 (figure 6-1)
to set second marker at beginning of sweep. Switching
c21 R92 R91 R90 RE9 to DELAYING SWEEP will show whichmarker is being
HIGH FREO .IMS 1MS tOMS lSEC
, displayed.
I ADJUST c
I SWEEP CALIBRATION (3) Set DELAY LENGTH to 10.00 cm. Adjust 9 cm
1 Delay R67 (figure 6-1) to set llthmarkerat beginning
of sweep. Adjustment of R63 and R67 interact. Re-
i peat as necessary,
I
I h. HIGH FREQUENCY ADJUSTMENT.
Complete steps f and g before performing high
frequency adjustment.
i (1) Reset controls on the Model 166D as follows:
SWEEP TIME ....... 50 microseconds/cm
SWEEP MODE ............. PRESET
TRIGGER SOURCE .............. INT
SWEEP SELECTOR. . MAIN SWEEP DELAYED
(2) Connect Time Mark Generator (50 psec mark-
ers) to oscilloscope Vert INPUT. Adjust DELAY
-- -r LENGTH to set leading edge of second marker at be-
C36
ginning of trace (approx. l cm). Increase DELAY
roo~sEc LENGTH reading by 9 cm. Adjust R92 to set leading
SWEEP CALIBRATION
I I edge of 11th marker at beginning of trace.
Figure 6-1. Location of Adjustments (3) Repeat (2) with DELAYING SWEEP TIME at 5
psec using 5 psec markers, Adjust C36(see figure
f. FREQUENCY COMPENSATION. 6-1).
( 1) Set oscilloscope SWEEP TIME to 1 millisecond/ (4) Check DELAYING SWEEP TIME accuracy (see
cm and SWEEP MODE to PRESET. table 6-3). Delaying sweep time calibration may have
(2) Set Model 166D controls as follows: to be changed slightly to meet specifications.
DELAYING SWEEP TIME ... 0.2 milliseconds/cm
SWEEP MODE .............. .FREE RUN 6-5. REMOVAL OF COMPONENTS AND
TRIGGER SOURCE ............... EXT SIIBASSEMRLIES.
SWEEP SELECTOR ..... .MAW SWEEP DELAY a. INTRODUCTION. The following paragraphs de-
DELAY FUNCTION .... .TRIGGER MAIN SWEEP
scribe the procedures for removal and replacement
DELAY LENGTH. ......... Greater than 1 cm.
of those subassemblies and components which may
(3) Observe sawtoothat cathode(pin 8) of V14A using require replacement or repair within the lifetime of
a compensated @ AC-21A probe and the oscilloscope the instrument and whose replacement is sufficiently
in which the Model 166D is installed. Adjust C1 until complicated to require instructions. Table 6-6 lists
adjustments required following tube, transistor and
bottom of sawtooth waveform is flat.
diode replacement. These adjustments may also be
required following component replacement in associ-
I ated circuits.
b. COMPONENT REPLACEMENT ON ETCHED
CIRCUIT BOARDS. The etched circuit boards used
in the instrument are constructed with eyelets for
01227-1 6- 5 |
ACEC
