Tektronix 2205, Руководство оператора

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Operation
To display Field 1 and Field 2 at the same time, connect the
same television signal to both the CH 1 and CH 2 inputs; set
VERTICAL MODE to BOTH and ALT; and set the SEC/DIV control
to 0 .5 ms or faster sweep speed.
If you magnify the vertical display beyond the graticule, the trig­
ger may be degraded. To avoid trigger overload, use either CH
1 or CH 2 for display and use the EXT INPUT channel with an
appropriate video signal as the trigger source. A composite
sync signal can be used for the trigger source as well as com­
posite video.
Source
Choose a single channel as the trigger source to correctly dis­
play the timing relationships between two channels. Choose the
channel with the lowest frequency signal to avoid ambiguous dis­
plays.
With TRIGGER SOURCE set to VERT MODE and VERTICAL MODE
set to ADD or CHOP, the triggering signal is the algebraic sum of
the Channel 1 and Channel 2 input signals.
Use a composite trigger source only to view asynchronous
signals simultaneously. To generate a composite trigger: select
VERT MODE TRIGGER SOURCE and BOTH-ALT VERTICAL MODE.
Slope
Use the SLOPE control to select either the rising ( _ /~ ) or the
falling ( ~ \_ ) edge of the signal to trigger the sweep.
Level
The LEVEL control gives you complete freedom to choose the
most appropriate threshold voltage on a signal to. initiate sweeps
whenever any trigger mode except P-P AUTO is selected.
CONNECTING SIGNALS
The signal adapter supplied with the instrument is usually the
most convenient way to connect a signal to the 2205. These
signal adapters are shielded to prevent pickup of electromag­
netic interference. When connected to the 2205 input, a signal
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2205 Operator’s