BBC Micro Model A/B General Maintenance: Difference between revisions

The '''BBC Micro Model A/B''' is a classic British microcomputer, now over 40 years old. Regular maintenance is essential to preserve its reliability, prevent avoidable failures, and ensure safe operation for years to come.

=== Case and Keyboard ===

* Clean edge connectors (user port, 1 MHz bus, Tube, Econet) with IPA and a lint-free swab.

The BBC Micro’s internal linear PSU is robust but can fail with age, especially due to capacitor degradation.

* Modern switch-mode replacement PSUs are available for the BBC Micro, but original units can be safely rebuilt.

Age and humidity can cause oxidation on edge connectors, sockets, and switches.

* Inspect for green or white corrosion, especially on the user port and cassette socket.

The BBC Micro contains both electrolytic and tantalum capacitors, some now well past their service life.

* Audio hum, loss of sound, or video sync issues

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=== Cassette Interface ===

* In hot environments, consider adding a low-noise 5V fan inside the case, powered from the user port (observe current limits).

* ESD wrist strap and anti-static mat

* Digital multimeter (for voltage and continuity checks)

* Diagnostic ROMs (e.g., “Test ROM”, “Acorn Diagnostic”)

# '''Inspect and replace RIFA X2 capacitors''' in the PSU before first power-up.

# '''Check all PSU output voltages''' (+5V, -5V, +12V) before connecting peripherals.

# '''Maintain good ventilation'''—keep vents clear and avoid stacking equipment.

* [[BBC Micro Model A/B Capacitor Replacement Guide]]

* [[BBC Micro Keyboard Repair]]