Before switching on a machine that has sat unused for years
Found an Amiga or a Spectrum in the loft? Don't switch it on just yet. Half an hour of checks stops a leaking battery, a power supply or a tired capacitor from turning a small fault into a big one.
Difficulty: EasyTime: 30 min
⚠ Before you start
- Never open a power supply that is plugged into the mains, nor the 230 V side of a power supply, even when unplugged: the capacitors can hold a dangerous charge.
- If you smell burning or see smoke when you switch on, unplug it from the wall socket immediately.
Why not switch it on straight away
A machine that is 30 or 40 years old has spent a long time out of use. Electrolytic capacitors dry out or leak, clock batteries may have spread corrosive liquid across the board, and old power supplies can deliver voltages outside the normal range. Switching on without checking means risking chips that are hard to find today.
Step-by-step check
Do this with the machine unplugged from the mains and with no power supply connected.
- 10Look at the outside of the case: cracks, marks from spilt liquid, signs that it has been kept somewhere damp.
- 20If it is an Amiga with a trapdoor memory expansion (A501, A601, A604), remove the bottom cover and check whether the expansion's battery has greenish or bluish crystals around it. If it does, don't switch on: see the guide on batteries.
- 30If you feel comfortable doing so, open the case and look over the main board for: batteries (blue or black cylinders soldered to the board), swollen capacitors or capacitors with residue around them, and greenish traces.
- 40Remove the dust with a soft brush. Don't use a vacuum cleaner directly on the board: it generates static electricity.
- 50Check the power supply before connecting it to the machine (see the guide on power supplies). On the Spectrum 48K, make sure it is the correct power supply and that the polarity is right.
- 60First power-up: switch on with no peripherals, no floppy disks or cassettes, and watch out for smells, crackling and how the picture behaves.
What is normal at start-up
On an Amiga, it is normal for the screen to go through shades of grey until it shows the hand holding a floppy disk (Kickstart 1.x) or the insert-disk animation (2.x and 3.x). If the screen stays a different colour, see the guide on start-up colours.
On a Spectrum 48K, the normal result is a white screen with the copyright message at the bottom. On the 128, +2 and +3 the start-up menu appears.
When to bring it to us
If you have found a leaking battery, swollen capacitors or signs of damp, or if the machine gives no picture at all, bring the machine in before trying again. The fewer times a faulty board is powered up, the less damage is done.
Request a repairThese guides are for information. Working on old electronics carries risks: do it at your own risk, with the machine unplugged, and never open power supplies or CRT monitors. If in doubt, bring the machine to us.