Tektronix 175, Руководство пользователя

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Circuit Description — Type 575
V143A
Cathode
t 150
F 50
-‘ 1.5
V172B
Cathode
2.4
1
V171
Grid
1.5
-1.9
r 54
V163A
Cathode
6
40
46
V143B
Cathode
74
0
5
V155B
Plate
25
2
V152B
Plate
7
Fig. 3-7. Time relationships between the Step Generator output waveforms (D)
and waveforms at key points in the step generator section.
Fig. 3-9 (a) is a diagram of a transistor operating as an
emitter follower. Fig. 3-9 (b) is the vacuum-tube equivalent
of the same circuit. Note that in both cases the output
signal is in phase with the input signal. The average value
of the output voltage may be set to zero by proper biasing
of the input.
Fig. 3-10 shows how an out-of-phase signal centered around
ground can be obtained with the same general configuration.
Note that only the ground point has been moved. The tran­
sistor is no longer operating as an emitter follower, but as
an ordinary voltage amplifier. The 100-ohm resistor is now
the collector load resistor.
The approximate positive and negative limits of the no-
load output voltage of Fig. 3-10 can be determined by con­
sidering the transistor as a switch which is either opened or
closed. When the switch is closed (emitter and collector
shorted), the output voltage must be +15 volts. When the
3-7