Model 405C Sect.IV Page 7
TABLE 4-2A. WAVEFORMS (CONT?D)
Oscilloscope Oscilloscope Normal
Test Point
Synchronization Sweep Speed Indication
I -L 1
9 Same as 7 20 ms/cm
Pin 6, V5
u
0 100 200
I + I
10 External at pin 1, V10 20 ms/cm
Pin 3, XZlA with input (negative-
going part of waveform)
-
0 10 20
11 Same as 10 20 ms/cm
+5~~
Pin 1, V13
-50
0 IO 20
12 Same as 10 20 ms/cm
Pin 1, V14 +5~~~
- 50
0 10 20
TABLE 4- 2B. TROUBLESHOOTING THE AMPLIFIER
Make sure all waveforms agree with those
shown in Table 4-2A before proceeding fur-
ther.
1) Connect an oscilloscope for external syn-
chronization (negative input) from pin 6, V8
of the Model 405C. Connect vertical input to
pin 7, V4 of Model 405C.
2) Momentarily depress the RANGE switch
until the instrument is on the +l volt range
(polarity sign and decimal light lit as shown
in the title page photograph).
3) Compare waveforms. If different, trouble
is in amplifier. Determine where waveform
SAMPLING RATE THYRATRON V8
first deviates from that shown. Arrows at I .
PHOTO CELL MULTIVI~RATOR vie .
bottom show time relationship of the opera-
tion cycle of the tubes called out by V num- RELAY CONTROL MULTIVIBRATOR, V9
B4,
bers. Comparison of point of deviation of
DELAY VIOm
waveform and time relationships will deter- RAHPMULTI I ?J7 ?
v5
mine faulty section. If you obtain proper OSC MULTl I 1, c.5-w
waveform but instrument still malfunctions,
check decade counters, oscillator gate multi-
vibrator or oscillator. |
ACEC
