Teledyne HDO9000, Руководство оператора

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HDO9000 High Definition Oscilloscopes Operator's Manual
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Post-trigger Delay , entered as a positive value, displays time following the trigger event. Post-
trigger Delay can cover a much greater lapse of acquisition time than pre-trigger Delay, up to
the equivalent of 10,000 divisions after the trigger event occurred (it is limited at slower
time/div settings and in Roll mode sampling). At maximum post-trigger Delay, the trigger point
is off the grid far left of the time displayed.
Set to Zero returns Delay to zero.
Real Time Sampling Rate
These controls specify how the instrument samples when in Real Time mode.
Sampling Rate / Maximum Sample Points is the number of samples taken per time division when
using a Fixed Sampling Rate. It changes to Maximum Sample Points, the number of samples taken
per acquisition, if you choose to Set Maximum Memory.
Set Maximum Memory automatically adjusts the sampling rate to take the maximum number of
samples possible given the amount of pre- or post-trigger Delay and the Time/div, up to the maximum
record length. This optimizes the sample rate for fast timebases when in Real Time mode.
Fixed Sampling Rate activates the Sampling Rate field for you to set your own rate. Lowering the rate
can extend the acquisition to accommodate slower timebases or longer delays.
Active Channels (Dual-Channel Acquisition)
The Active Channels settings allow you to combine the acquisition capabilities of the leftmost pair of
channels (C1 and C2) and the rightmost pair of channels (C3 and C4) to result in two channels with
maximum sample rate and memory.
In 4-channel mode, all channels remain active at the default sample rate.
To combine channels, under Active Channels, choose
2 or Auto :
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2-channel mode turns off acquisition on Channels 1 and 4. Channels 2 and 3 acquire at doubled
sample rate and memory.
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In Auto mode, the oscilloscope will allot the maximum memory and sample rate possible
based on the activity within each pair of channels. As long as only one channel in each of the
C1-C2 and C3-C4 pairs is turned on, the maximum rate is used. Turning on both channels in
either pair has the same effect as selecting 4 Active Channels.
Example: C1 can operate with either C3 or C4 at higher sample rate and memory since they
belong to different pairs, and likewise C2. However, C1 cannot operate with C2 without dropping
the sample rate, nor can C3 operate with C4.
Refer to Acquisition System in the product datasheet for maximum sample rates.
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