Tektronix 2245A Operator's Manual page 35

readout. Whenever A MODE is selected, the A/B SELECT switch is
set to A Trigger.
ALT—Alternates between A sweep (with an intensified zone repre­
senting B sweep) and B delayed sweep. Both A and B SEC/DIV switch
settings are displayed in the crt readout, but only the B can be
adjusted. Whenever ALT MODE is selected, the A/B SELECT switch
is set to B Trigger.
The B sweep speed cannot be set slower than the A sweep speed;
attempting to do so forces the A sweep speed to follow the B sweep
speed. To increase the A sweep speed in the ALT MODE, set the
Horizontal MODE to A, adjust the SEC/DIV switch to a faster A sweep
setting, and reset the Horizontal MODE switch to ALT. The B sweep
speed and the length of the intensified zone are determined by the B
SEC/DIV switch setting.
B—Selects B sweep horizontal deflection. The B sweep speed is de­
termined by the B SEC/DIV switch setting as displayed in the crt
readout. Whenever B MODE is selected, the A/B SELECT switch is
set to B Trigger.
The start of the B sweep in RUNS AFTER mode (or the arming of the
B Trigger in any triggered mode) is delayed from the start of the A
sweep by a time determined by the setting of the |<- OR DELAY con­
trol. The B SEC/DIV switch setting and the Delay Time Position set­
ting are displayed in the crt readout. A greater-than sign (>) is dis­
played in front of the Delay Time readout if the B Trigger MODE is not
RUNS AFTER.
X -Y —The signal applied to CH 1 OR X input connector produces the
horizontal (X-Axis) deflection. Signals applied to any vertical input
connector or ADD may be selected to provide the vertical deflection
(Y-Axis).
The X-Y displays are horizontally positioned by the Horizontal POSI­
TION control and vertically positioned by the associated vertical chan­
nel POSITION control.
(2?) A AND B SEC/DIV S w itch —Selects the horizontal deflection rate
(sweep speed) for both the A sweep and tht. B sweep in a 1-2-5
sequence. Calibrated sweep speeds are obtained with the A and B
SEC/DIV VAR control in the detent (fully clockwise) position. The A
SEC/DIV switch setting is set only from the A Horizontal MODE and
the B SEC/DIV switch is set only from the ALT or B Horizontal MODE.
2245A Operators
Controls, Connectors, and Indicators
2-9