2. DISCLAIMER

Using the methods / circuits / components as described in this document is entirely at your own risk.

If you damage your PC / Joystick / Keyboard / Yourself by any of the things I wrote down in this document, it’s NOT MY FAULT.

Having said that, here are some tips to limit the damage:

1. Switch of the power and UNPLUG the mains cord(s) when doing soldering in mains powered equipment. If you don’t, you may find out the hard way: Most PC appliance and peripherals’ power supplies contain Y-capacitors. If you do not have too good grounding (like here in Taiwan), equipment circuits will "float" between ground and mains, even when the (soft) power switch is off. Touching sensitive pins with a soldering iron will produce a small spark, effectively killing electronics connected to it.

When plugging / unplugging signal cables between two mains powered equipment, the same can happen. I had my printer electronics damaged this way.

2. BE CAREFUL with power tools. Use stable workbenches and vises to hold stuff. Wear glasses when doing high-speed wood cutting or grinding. Have somebody help when cutting large boards on a table saw. Count your fingers afterwards.

3. Soldering irons are hot, but you’ll survive. Torches are very hot and have long heat beam, far exceeding the flame length. If you are careless, you may loose your hair and more.

4. KEEP AWAY from the mains voltage. Use power supplies that have good mains isolation and safety measures to avoid touching. Never grab near mains voltage terminals with both hands.

120V is nasty, 240V is VERY nasty!

5. Before powering up your newly build circuit, check & double check the wiring, especially the plus and minus supply connections. For small signal circuits, use supplies with some current limiting, like a 10 Ohm resistor in series with the positive supply line. Use IC sockets to avoid re-soldering the whole board after blowing up one part.

Put fuses (1 Amp or so) into your system, especially when using circuits driven from your PC +5V supply. Otherwise, your circuits and wiring may literally go up in smoke.

6 . Try to keep your circuits isolated from the PC. Using relays and opto-couplers is a good way to achieve isolation. Exceptions are the game port and USB stick circuits. Clean soldering, strain relieve on cables, isolation on bare leads will help avoid shorts.

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