Teledyne HDO9000, Руководство оператора

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Acquisition
Clock Source Settings
An external reference clock, applied via the REF In input, is used to synchronize the instrument's
internal timebase to an external frequency source. This allows multiple instruments to lock their
timebases to a common source.
An external sampling clock, applied via the EXT input, replaces the internal timebase as the sampling
clock. This means that the external sampling clock controls when the digitizers sample the input
waveforms.
Since the external sampling clock uses the EXT input, an external trigger cannot be used when the
external sampling clock is in use.
Clock Frequencies
The signal types, frequency ranges, and levels accepted for an external reference clock or sampling
clock are model dependent. See the product specifications at teledynelecroy.com .
Reference Clock
The default setting is to use the instrument's Internal 10 MHz clock. To use an external reference
clock:
1. Connect a clock source to the Ref In 10 MHz input using a BNC cable.
2. Go to Timebase > Horizontal Setup and choose Real-Time Sampling Mode .
3. On the Clock Source tab under Reference Clock choose External .
Sample Clock
The default setting is to use the instrument's Internal clock. To use an external sample clock:
1. Connect a clock source to the EXT input using a BNC cable.
2. Go to Timebase > Horizontal Setup and choose Real-time Sampling Mode .
3. On the Clock Source tab under Sample Clock choose from 0V, ECL, or TTL pulse types.
4. Choose an External Coupling that matches the clock source input impedance.
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