TROUBLE SHOOTING

What to do if it Doesn't work?

• Carefully check that the components are fitted correctly. Check that all the components are in the right place.
• Check the colours of resistors against the component sheet, it is easy to mix them up. Pay particular attention to electrolytic capacitors, LEDs and battery snaps. Are they the right way around?
• Check that transistors haven't been soldered into the board backwards.
• Check all your soldering. A good solder joint looks shiny and smooth and covers the hole completely.
• Hold your board up to the light. If any light shows through a hole then more solder is needed.
• Check that large blobs of solder are not causing short circuits, particularly with chip sockets. If too much solder has been used it is often better to remove it completely using a desoldering pump and then re-solder.
• Also check for streaks of solder bridging tracks, and any hairline cracks in tracks. Hairline cracks can be repaired by soldering over the gap.