Tektronix 80A00, Руководство по обслуживанию

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Theory of operation
Rear panel The removable hard drive contains the product software and operating system
software. It also provides capability to store and access waveform data. The GPIB
allows for external control of the instrument.
You can make hard copies on the GPIB and RS-232 ports. Other ports are
outputs from the ATX board: DVI-I, USB (4), sound, serial, Ethernet, mouse,
and keyboard.
Low voltage power supply The low voltage power supply is a switching power converter with active power
factor control. It supplies power to all of the circuitry in the instrument.
The principal POWER switch, located on the rear panel, controls all power to the
instrument including the Low Voltage Power Supply. The ON/STBY switch,
located on the front panel, also controls all of the power to the instrument except
for part of the circuitry in the Low Voltage Power Supply and stand-by power on
the motherboard.
The power supply sends a power fail (~PF) warning to the processor system if the
power is going down.
Fans The fan assembly provides forced air cooling for the instrument. The fans are
controlled by the PPC processor.
Electrical sampling modules
80E01, 80E02, 80E03,
80E03NV, 80E04, 80E06,
80E07/B, 80E09/B, 80E11,
80E11X1 sampling
modules (nonTDR)
For two-channel electrical modules, a single strobe, delivered from the instrument
mainframe to both acquisition channels, controls the timing of the strobe assertion
to both channels. If channel-to-channel deskew is zero and the channel delays
(if equipped) are matched, the sampling coincidence between channels is very
close. Acquisition deskew function is accomplished either by making separate
acquisitions over individual acquisition windows or by adjusting Channel Delay
(if equipped).
For one-channel electrical modules, an individual strobe delivered from the
instrument mainframe to the acquisition channel controls the timing of the strobe
assertion to the channel. Acquisition deskew function is carried out by moving
the strobe timing for the channel to a unique acquisition window or by adjusting
Channel Delay (if equipped).
Most electrical channels feature a Tekprobe Level 2 probe power connector for
attachment of a real time probe. The control of this probe is a mainframe function.
All module calibration signals are derived from a 2.5 V precision voltage reference
internal to the sampling module. Settings derived from this reference are stored in
a nonvolatile EEPROM in the sampling module, although the responsibility for
the execution of these settings is with the mainframe.
6 DSA8300 Digital Serial Analyzer and Modules Service Manual