Tektronix 2221 - Page 19

General
Information -
2221
Operators
Table
1-2 (
cont
)
O
Characteristics
Performance
Requirements
TRIGGERING
SYSTEM
П
П
П
M
П
1
П
П
TRIGGER
Sensitivity
P - P
AUTO
and
NORM
Internal
External
10 MHZ 60 MHZ
0.35 div
1.0 div
40
mV 120 mV
External
trigger
signal
from
a
50 -
ohm
source
driving a 50 -
ohm
coaxial
cable
terminated
in
50
ohms
at
the
input connector
.
Reduces
trigger
signal
amplitude at high
frequencies by
about
20 dB with
rolloff
beginning at 40
kHz + 15 kHz .
Should not
trigger with
a 1 -
division
peak
- to -
peak
250
kHz
signal
when HF
REJ is ON .
HF
REJ
Coupling
P - P
AUTO
Lowest
Useable
Frequency
20 Hz with 1 division internal or 100 mV external.a
TV
LINE
Internal
0.35 div.a
External
2
35
mV
p -
p .
> 1 division of composite sync , a
TV FIELD
EXT INPUT
Maximum
Input
Voltage
A
400 V ( dc + peak ac ) or 800 V ac p - p at 10 kHz or less.a
See
Figure
1-1
for
maximum
input
voltage vs
frequency
derating
curve ,
1 M2
+ 2 % .a
20 pF 2.5 pF.a
Input
Resistance
Input
Capacitance
AC
Coupled
Lower
Cutoff
Frequency
LEVEL
Control
Range
TRIGGER (
NORM )
INT
10 Hz or less at -3 dB a
П
п
П
П
П
1
EXT ,
DC
EXT , DC - 10
VAR
HOLDOFF Control
(
NON
STORE )
May be set to any voltage level of the trace that can be displayed.a
At
least
+1.6 V ,
3.2
V
p - p .
At least +16 V , 32 V p - p.a
Increases Sweep holdoff time by at least a factor of 10.a
See "
VAR
HOLDOFF
Control
" in
Section
3
, "
Controls ,
Connec
tors , and Indicators " for effect in STORE Mode ,
Acquisition Window Trigger Point
Pretrigger
Seven - eighths of the waveform acquisition window is prior to the
trigger.a
Posttrigger
One - eighth
of the
waveform
acquisition
window
is
prior to the
trigger .
One - half
of the
waveform
acquisition
window is prior to
the
trigger.a
Midtrigger
& Performance Requirement not checked in manual .
C
П
П
1-7