D . S E T T I N G T H E C L O C K
1 .
Setting the clock
When all the m etal plates are first inserted into the potatoes, the LE D
screen will light up and will show a static display of “ 12 :0 0 ” .
Press A once, the clock will start working. You will see the tw o dots in the
m iddle start flashing.
Press B twice to obtain the set month mode, then press A to adjust to the right m onth. Press B to confirm an d the
display will switch to the set day mode.
Press A to adjust to the right day. Press B to confirm and switch to the set hour m ode.
Press A to adjust to the right hour. Press B to confirm and sw itch to the set m inute mode.
Press A to adjust to the right m inute and press B to confirm.
After th e m inute is confirmed, press A once. Th e set time will be displayed.
2 .
Viewing the clock
By default, the clock display shows the current tim e.
To view the Date: Press A once. The clock display will resume showing the current tim e after 2 seconds.
To view the seconds, press A twice. To resume th e current tim e, press A a g ain .
If your potato clock produces a weak display, try one of the following:
1 . Give it tim e, the signal is sometim es weak a t the beginning, but gets stronger after a short while.
2 . Exam ine the metal plates fo r rust (oxidization). Use sand paper to remove any rust.
3. Try putting the m etal plates closer together (but not touching each other). Conduction will be better if the distance
between the plates is shorter.
4 . If there is no reaction whatsoever, check all the connection points. M ake sure th a t the connection points are
correctly and firmly placed. A lso , check if the polarities are correct - make sure th a t the negative (black wires) and
positive (red wires) term inals are connected properly.
5 . Check if the metal plates/wires are touching each other, th is causes short circuits.
The m etal strips and potatoes make a simple battery tha t creates the electricity to operate the clock. Ea c h potato
works as a device called a electrochemical cell. It converts the chemical energy stored in the metal strips into
electrical energy. Two potatoes are needed to make electricity strong enough to run the clock.
A cell works because of the chemical properties of the m etals inside (in th is case th e copper and zinc). The different
properties cause tiny particles charged with electricity (called ions) to move between the tw o strips of m etal. This
flow is an electric current. Th e potato contains the particles th a t allow th e current to flow, but it stops th e metals
touching. Electric current also flows along th e wires between the zinc and copper strips an d the clock. Th is current
makes the clock work.
E . T R O U B L E S H O O T I N G
F. H O W I T W O R K S