Fluke PM6690, Service Manual, Page: 3 / 200

GENERAL INFORMATION
Method of Notation
This manual contains directions and information that apply to the PM6690 Timer/Counter/Analyzer. In order to simplify the references,
the following designation system is used throughout the manual:
– PM6690 is abbreviated to '90' .
Warranty
The Warranty Statement is included in the Getting Started Manual.
Declaration of Conformity
The complete text with formal statements concerning product identification, manufacturer and standards used for type testing is avail-
able on request.
Hardware Versions
This Service Manual provides Source of Supply information for the Fluke Model PM6690 Timer/Counter/Analyzer, which may con-
tain an OLD version of the Main CCA, called Version A, or a NEW version of the Main CCA, called Version B. Both the old and the
new version of the Main CCA have the same part number. All orders for the old version of the Main CCA will be filled with the new ver-
sion of the Main CCA. When the old version of the Main CCA is returned to the factory for repair, the new version of the Main CCA
will be returned in place of the old version of the Main CCA, if the microprocessor has to be replaced.
Devices with serial numbers up to and including 916779 are equipped with a Triscend microprocessor, whereas devices with higher se-
rial numbers have a Sharp microprocessor. Both are based on an ARM7 core, and from the operator’s point of view the behavior is not
affected. However, essential parts of the main PCB differ, and the corresponding sections of the service manual are consequently af-
fected. Even though large parts of the hardware are common to both versions, we have preferred to divide the pertinent chapters into
separate sections, where certain parts are repeated, all in order to improve legibility and simplify troubleshooting.
Version A refers to devices equipped with the Triscend microprocessor.
Version B refers to devices equipped with the Sharp microprocessor.
The chapters that need special attention are:
Chapter 4, Circuit Descriptions
Chapter 6, Repair
Chapter 8, Replacement Parts
Chapter 9, Schematic Diagrams
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Firmware Compatibility
Despite the relatively large hardware differences, we have managed to integrate the firmware, so that future upgrades can be applied to
both versions by means of the same hex file. Thus there is no need to check the serial number or else find out which processor is inside
the cover. Just proceed according to the instructions given in Chapter 5, Corrective & Preventive Maintenance.
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