Tektronix TYPE 109 Instruction Manual page 37

Collector
Q725
100 V SET
F ig . 6 - 4 . R ig ht sid e v ie w , fro n t portio n o f the T yp e 1 0 9 , sh o w in g
the lo catio n of the in te rn a l ad ju stm en ts an d the test p o in t.
2. Check Power-Supply Regulation and Ripple
a. Using the information given in Table 6-2, connect
the VOM to the regulated supply under test to mon­
itor the voltage.
b. Connect the conventional test oscilloscope with the
high-gain plug-in unit and IX probe to the appro­
priate test point so the ripple amplitude can
checked simultaneously.
TABLE 6-2
Power Output V o ltag e
Supply* and Tolerance
± 1 0 0 V — 100 volts, ± 0 .5
volt
(regulated)
± 1 0 V + 10 volts, ± 1 volt
(regulated)
+ 17 V Approx. 15.5 to 18
(unreg.) volts (does not have
to be monitored)
*Fig. 6-3 shows the test point locations.
**lgnore the superimposed spikes on the waveform.
c. Vary the output of the autotransformer between 105
and 125 (or 210 and 250) volts and check for proper
regulation and ripple amplitude within the line volt­
age operating range.
d. Set the autotransformer for an output of 117 (or 234)
volts.
e. Disconnect the VOM and the IX probe.
be
1 20 cps Ripple
Am plitude**
( p e ak-to -p e a k m ax.)
10 millivolts
100 millivolts (Measure
at emitter of Q627*)
1.8 volts
3. Check Frequency Range and Amplitude
a. Set the front-panel controls on the conventional test
oscilloscope to the following settings:
Input coupling
Volts/Cm
Variable Volts/Cm
Stability
Triggering Mode
Triggering Slope
Time/Cm
Variable Time/Cm
Horizontal Display
b. Disconnect the 1 X probe from the input of the oscil­
loscope and connect a 10 X
c. Connect the probe tip to the collector of Q725 (see
Fig. 6-3).
d. Adjust the oscilloscope controls to obtain a stable
display.
e. First, rotate the FREQUENCY control (see Fig. 6-4)
fully clockwise and check the waveform according to
the data given in Table 6-3 and Fig. 6-5. (Use the
graticule markings on your test oscilloscope to de­
termine the period and amplitude of the waveform.)
TABLE 6-3
Setting of Period
FREQ U EN CY (at 1
m illise c/cm )
Control
(1 ) Fully clock- 2.77 cm or
less
wise
3.6 cm or
(2) Fully coun-
more
ter clock-
wise
f. Then, rotate the FREQUENCY control fully counter­
clockwise and check the minimum frequency range
based on the information given in Table 6-3 and
Fig. 6-5.
g. Disconnect the probe.
F ig . 6 - 5 . W a v e fo rm m easu rin g p oin ts.
Calibration— Type 109
DC
1 Volt
Calibrated
Preset
AC
+
1 Millisec
Calibrated
Normal ( X I )
probe in its place.
M ultivibrator W aveform
Frequency Am plitude
(ty p ic a l)
18 volts
360 cps or
more
12 volts
275 cps or
less
6-3