HP 1740A - Page 14

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INFUT. BNC connector to apply external
signals to the channel A (Y) and channel
B (X) amplifier. Impedance and coupling
are selectable by@. Do not apply more
than 250 V (dc + peak ac) or more than
500 V p-p ac at 1 kHz or less.
POSN. Controls the vertical position of the
display.
CAL 1 V. Provides a 1-V_ peak-to-peak
(within 1%) square-wave voltage signal
recurring at an approximate rate of 1.4
kHz (100 mV _ peak-to-peak when termi-
nated in 50Q).
GROUND POST. Convenient chassis ground
connector. Useful to ensure a common
ground with equipment under test.
POSITION. Coarse @ and FINE @ad-
justments position the display horizontal-
ly.
AUTO/NORM. AUTO sweep mode (push-
button out). A free running sweep provides
a bright display in the absence of a trigger
signal.
NORM sweep mode (pushbutton in)
requires an internal or external signal to
generate a sweep and must be used if the
input frequency is less than 40 Hz.
SINGLE. Sweep occurs once with the same
triggering as in NORM. After each sweep,
the trigger circuit must be manually RE-
SET@.
RESET. Momentary pushbutton that arms
the trigger circuit in the single-sweep
mode. After pressing RESET@, the sweep
can be triggered by an internal or exter-
nal trigger signal or by rotating the TRIG-
GER LEVEL control @ through zero.
Reset Lamp. When lit, indicates the trigger
circuit is armed. Lamp goes off at the end
of the sweep and remains off until the
trigger circuit is again armed by pressing
the reset button.
MAIN. Selects main sweep for horizontal
display. Sweep rate and triggering are
selected by the main-sweep controls @ -
®.and © -O©.
@
A VS B. Selects an X-Y mode of operation
with channel A input (Y-axis) plotted
versus channel B input (X-axis). Vertical
positioning is adjusted by channel A
POSN@), and horizontal positioning is
adjusted by POSITION @ and FINE@.
OPTION 101. Deletes the A VS B function
and adds logic state display. When the
Model 1740A is connected to a HP Model
1607A Logic State Analyzer, pressing
STATE DSPL @displays a 16-word
table of 16-bit words.
MAG X10. Magnifies the horizontal display
10 times, and expands the fastest sweep
time to 5 ns/div, maintaining a sweep
accuracy within 3% at room temperature.
MAIN TIME/DIV. The inner knob controls
the main-sweep rate, which is indicated by
the numbers displayed in the knob skirt
opening. Sweep accuracy is within 2% (un-
magnified) at room temperatures.
DLY'D TIME/DIV. The outer rotating
section selects the delayed-sweep rate,
which is indicated by the marker on the
outer knob. Sweep accuracy is the same as
with MAIN TIME/DIV. An interlock is
incorporated so the delayed sweep is al-
ways faster than the main sweep. When
rotated out of the off position in the MAIN
mode@, a portion of the main sweep is
intensified indicating the length and delay
position of the delayed sweep with respect
to the main sweep.
SWEEP VERNIER. Provides continuous ad-
justment of main sweep TIME/DIV bet-
ween calibrated positions, extending the
slowest sweep to 5 s/div.
UNCAL. Lights when SWEEP VERNIER
@ is out of the CAL detent position, and
indicates that the sweep is not calibrated.
TRIGGER HOLDOFF. Increases the time
between sweeps and aids triggering on
complex displays such as digital words.
TRIGGER LEVEL. Selects the voltage level
on the input trigger signal where the sweep
is triggered. With external trigger signals,
the trigger level is continuously variable
from +1.5 V to —1.5 V on either slope of
the input trigger signal; +15 V to —15 V in
EXT = 10 a5} mode. With internal trigger
signals, the trigger level selects any point
on the vertical waveform displayed.
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oO
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O«®@
Ms BE ss)
POS/NE
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sweep.
LF REJ
trigger s
This is
signals
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such as
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trigger s
This is
signals
nating
such as
LINE. §
REJ @
INT @®
circuit ¢
signal f
AC/DC.
below a
INT/EX’
nal vert
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signal |
put for
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EXT = °
or @ ir
EXT TR
trigger
mately
mately
250 V |
1 kHz o
DELAY.
variable
MAIN’
DLY'D.
tal disp