Acorn BBC Master 128, Руководство по обслуживанию

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Master Series Service Manual
7.16 Cartridge port
7.16.1 Causes the sound output to be noisy.
1 Check the cartridge for shorts and general layout.
7.16.2 Will not recognise some cartridges.
1 Is the cartridge for the Electron? Not all of these are compatible.
2 Are all the links assocciated with the cartridge in the correct
position.
3 Is the cartridge edge connector excessively worn, e.g. gold plating
worn through?
4 Are all connections to the edge connectors correct without shorts to
each other?
5 Are any of the edge connector blades bent or worn? If so, the
connector must be replaced.
7.17 Econet
Econet can only be serviced properly by Econet service centres, who
will have the necessary test equipment to check the system thoroughly.
However, there are a few simple things which can be checked without
the test equipment. Follow the Econet board circuit diagram in the
Appendix.
1 Check that the two connectors on the Econet module are correctly
inserted. The longer connector has two spare pins on the left of the
PCB socket. If the module is displaced and is plugged into one or both
of these spare pins, it will not work.
2 Check that the Econet module is installed and fitted correctly.
3 Check that NMI on the CPU pin 6 IC14 (TP 3) is not being held low.
49 Issue 1