Tektronix 2215, Instruction Manual

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charging prevents large trace shifts o f the display when
switching fro m GND to AC coupling.
Each channel o u tp u t signal from the A tte n u a to r c ir­
c u itry is applied to the Vertical Pream plifier c irc u itry fo r
fu rth e r am p lifica tio n . The Channel 2 Pream plifier includes
an Invert feature th a t allows the operator to invert the
Channel 2 signal display on the cathode-ray tube (crt).
Trigger P ic k o ff A m p lifie rs in each channel supply an
internal trigger signal fro m either channel signal or fro m
both channels to the Internal Trigger A m p lifie r in the
Trigger c irc u itry .
Each channel signal is selected fo r display in tu rn by the
Channel Switching Logic c irc u it under co n tro l o f the
front-panel V E R T IC A L MODE switches. The o u tp u t signal
from the Channel Switching Logic c irc u it is applied to a
Diode Gate circ u it. The Diode Gate c irc u it switches either
channel signal (or both signals fo r A D D ) to a Delay Line
Driver stage th a t supplies the proper drive and impedance
match to the Delay Line. The Delay Line produces approx­
im ately 100 ns o f delay in the vertical signal to allow the
Horizontal c irc u itry tim e to produce the necessary sweep
to display the signal.
Final a m p lifica tio n o f the vertical signal is supplied by
the Vertical O u tp u t A m p lifie r. The Vertical O u tp u t
A m p lifie r supplies the required signal levels necessary to
produce vertical deflection o f the electron beam in the crt.
The A /B Sweep Separation c irc u itry supplies a dc-offset
current to the Vertical O u tp u t signal w hich is used to
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