| Fuse |
|
Is a thin wire which breaks if there is too much current from a short
circuit or other problem. |
| Battery |
|
Produces electric energy from chemical energy. |
| Resistor |
|
Slows the flow of electric current |
| Variable resistor |
|
Like a regular resistor, but adjustable. Often used as volume controls. |
| Earth ground |
|
A connection from the the radio to the earth, usually through a copper
pipe driven into the soil. |
| Chassis ground |
|
A connection of the negative side of the electronic circuit to the frame and
case that holds of the equipment. |
| Capacitor |
|
Stores an electric charge. Will let alternating current (AC - like in your house)
flow but stops direct current (DC - like from a battery). |
| Variable capacitor |
|
Same as a regular capacitor, but adjustable. Often used as tuning controls. |
| NPN transistor |
|
Amplifies a current. (NPN is remembered as Not Pointing iN) |
| PNP transistor |
|
Amplifies a current. (PNP is remembered as Pointing iN) |
| Coil |
|
Also called a choke, it works the opposite of a capacitor. It lets DC flow but stops
AC. |
| Tube |
|
A vacuum tube made of glass with wire filaments inside. Amplifies a current. It
has been replaced by transistors in most home equipment, but is still found in some high power radio transmitters. |
| Antenna |
|
Sends radio frequency signals into the air. |
| SPST switch |
|
Single-pole single-throw switch. Has two positions, on and off. (Most light
switches) |
| DPDT switch |
|
Double-pole double-throw switch. A double-throw switch has three positions. It can
switch one input to one of two outputs - sort of like the switch you put on your television to switch between watching TV
and playing your video game. The double-pole means it can switch a pair of inputs to either of two pairs of outputs. |
