Tektronix TDS5000B Series, Онлайн руководство пользователя

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By default:
ƒ
TTL fixes the trigger level at +1.4 V
ƒ
ECL fixes the trigger level at –1.3 V
When you set the volts/div less than 200 mV, the instrument reduces the TTL or ECL trigger
levels below their standards. This is because the trigger level range is fixed at
±
12 divisions from
the center. For example, at 100 mV, the trigger range is
±
1.2 V, smaller than the standard TTL
and ECL levels
.
All preference settings are saved when you turn the instrument power off.
User Preferences: Record Length
Access this control window from the Utilities menu User Preferences command.
Overview
Use the Record Length tab to define how the instrument responds to changes in record length.
To Use
Click one of the buttons to define which variable will be held constant when the record length
changes.
Behavior
Record length, sample rate, and horizontal scale are dependent variables. When you change the
record length, you can choose to hold either the sample rate or the horizontal scale constant. The
remaining variable will change in response to the record length changes.
All preference settings are saved when you turn the instrument power off.
User Preferences: Readouts
Access this control window from the Utilities menu User Preferences command.
Overview
Use the Readouts control window to select a transparent or opaque background and turn Highlight
readouts on and off.
To Use
Click Transparent to set the readout background to transparent. Click Opaque to set the readout
background to opaque.
Click Changes On to highlight readouts when you make changes. Enter the time to leave the
readout highlighted in the Hide After text box.
Behavior
When the readout background is set to transparent, the readouts appear behind the waveform.
When the readout background is set to opaque, the waveform appears behind the readouts.