Tektronix 2215, Instruction Manual

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allow ing on ly the A Sweep to be passed to the Horizontal
A m p lifie r. In B H O R IZ O N T A L MODE, U696B pin 10 is
HI and pin 13 is LO, holding U696B reset and allowing
only the B Sweep to go to the H orizontal A m p lifie r.
W ith S650 set to A L T and the CH 1-BOTH-CH 2 V E R ­
T IC A L MODE switch set to CH 1, all o f the fo llo w in g pins
are H I: U670D pin 13, U690D pin 9, U690E pin 11, and
U 670A pin 2. The resulting LOs applied to the inputs o f
U693D from the outputs o f U690D and U690E cause the
o u tp u t o f U693D (pin 11) to be LO. This LO is inverted by
U690F, causing pin 10 o f U693C to be HI. Since U696B is
n o t held either set or reset (pins 10 and 13 are both H I),
the o u tp u t state w ill reverse (toggle) whenever a clock pulse
is received on pin 11. Negative-going transistions o f the A lt
Sync signal w ill cause the o u tp u t o f U670D to go H I, w hich
transfers through U693C, clocking U696B. W ith each A lt
Sync pulse, the outputs o f U696B w ill toggle to alternately
enable the A and B Sweeps to reach the H orizontal A m p ­
lifie r. For the CH 2 position o f the V E R T IC A L MODE
switch, c irc u it operation is the same except th a t U690E pin
11 is LO. Whenever the B Sweep is selected fo r the H o ri­
zontal A m p lifie r, U696B pin 8 w ill be HI. This HI is applied
to U 670A pin 1, and since pin 2 is also HI, o u tp u t pin 3
(Sep) w ill go LO to enable the A /B Sweep Separation
c irc u itry (Diagram 3).
When the V E R T IC A L MODE CH 1-BOTH-CH 2 switch
is set to BOTH, the AD D -A LT-C H O P switch becomes
functional. In the V E R T IC A L MODE A L T position, the
fo llo w in g conditions are present: the V a lt signal is LO,
the Halt signal is H I, and the CH 1 Sel signal is a T T L
square wave th a t switches states at the end o f the A Sweep.
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