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Theory of Operation
3- 2
TDS 420A, TDS 430A & TDS 460A Service Manual
For example, if 50
Ω
input termination is selected and the input is overloaded,
the processor system switches the input to the 1 M
Ω
position. The preamplifier
in the A05 Attenuator amplifies the input signals.
Probe Coding Interface.
Probe coding interface signals pass through the
A06 Front Panel to the processor system.
Jumper.
Signals from the attenuators pass through the A08 Jumper board to the
acquisition system.
Acquisition System.
The acquisition system converts the analog input signals to
digital signals and controls the acquisition process under direction of the
processor system. The acquisition system includes the trigger, acquisition timing,
and acquisition mode generation and control circuitry.
D1 Bus.
The acquisition system passes the digital values representing the
acquired waveform through the D1 bus to the A09 DSP board (TriStar). This
happens after a waveform acquisition is complete if the digital signal processor
(DSP) requests the waveform.
Processor System.
The processor system consists of a 68020 microprocessor that
controls the entire instrument. It includes the firmware program for the oscillo-
scope. The firmware can be reprogrammed by using the GPIB and an external
software package. The processor system also includes a GPIB interface. The
processor can display text and symbols (that is, cursors, but not waveforms) by
passing them to the A02 Display board.
DSP.
The digital signal processor processes each waveform as directed by
software downloaded from the system processor. Waveforms to be displayed are
passed on to the A02 Display board.
Display.
Text and waveforms are processed by different parts of the A02 Display
circuitry. The display sends the text and waveform information to the A26 Moni-
tor assembly as a video signal. The display circuitry also generates and sends
vertical (VSYNC) and horizontal (HSYNC) sync signals to the A26 Monitor
assembly. A VGA-compatible video output is available at the rear of the
oscilloscope.
Содержание TDS 420A
Страница 16: ...Service Safety Summary xii TDS 420A TDS 430A TDS 460A Service Manual ...
Страница 36: ...Nominal Traits 1 14 TDS 420A TDS 430A TDS 460A Service Manual ...
Страница 44: ...Warranted Characteristics 1 22 TDS 420A TDS 430A TDS 460A Service Manual ...
Страница 54: ...Installation 2 6 TDS 420A TDS 430A TDS 460A Service Manual ...
Страница 64: ...Operating Information 2 16 TDS 420A TDS 430A TDS 460A Service Manual ...
Страница 72: ...Performance Verification Procedures 4 4 TDS 420A TDS 430A TDS 460A Service Manual ...
Страница 160: ...Maintenance 6 8 TDS 420A TDS 430A TDS 460A Service Manual ...
Страница 226: ...Removal and Installation Procedures 6 74 TDS 420A TDS 430A TDS 460A Service Manual ...
Страница 243: ...Troubleshooting TDS 420A TDS 430A TDS 460A Service Manual 6 91 J2 Pin 1 Figure 6 42 A02 Display Connector J2 ...
Страница 260: ...Options and Accessories 7 6 TDS 420A TDS 430A TDS 460A Service Manual ...
Страница 262: ...Electrical Parts List 8 2 TDS 420A TDS 430A TDS 460A Service Manual ...
Страница 272: ...Diagrams 9 10 TDS 420A TDS 430A TDS 460A Service Manual ...
Страница 287: ...TDS 420A TDS 430A TDS 460A Service Manual 10 15 1 2 3 4 5 6 7 3 8 9 10 11 Figure 10 5 Cables and routing B080000 Up ...