You will need
  • The vessel (this may be a plastic bottle), 150-250 ml of water, salt, two wires.
Take a prepared vessel and fill it with water. Keep in mind that the liquid must not be too much. It should occupy about half the container or less. Thus, 250 ml of water is perfect for a half-liter bottle.
Pour in water about 2-4 teaspoons of salt (that is, this amount of sodium chloride that can dissolve in water). Water & salt are the electrolytes.
Take the cable with the plug. Strip on one of the wires is a fairly large part. Another option is to hang a metal electrode of small size.
Dip the wire in water solution with sodium chloride, i.e. in the electrolyte.
Attach the second wire of the thermocouple.
Connect the wires directly to the socket, pre-limiting the current. Supply tube of about 6-10 amps before to carry out the operation.
Dip the thermocouple in the electrolyte. You will be able to see between the surface of salt water and a wire formed arc. The evaporation of water, will spray, so you need to be very careful. Keep requires approximately 2-4 seconds.
Remove the thermocouple from the electrolyte.