SCIENCE FAIR

KITS FOR BUILDING ELECTRONIC AND ELECTROMECHANICAL DEVICES-NAMELY, RADIOS, MICROPHONES, POWER SUPPLIES, OSCILLATORS, AMPLIFIERS, LIGHT GENERATION DEVICES, SIRENS, BURGLAR ALARMS, BELL OR BUZZER CODE KEYS, TELEPHONE PICK-UPS, FIRE ALARMS, VOICE CONTROL RELAYS, SPEAKERS, NIGHT LIGHTS, INTERCOMS, LIGHT OPERATED ALARMS, SOLAR OPERATED ALARMS, SOLAR OPERATED RADIOS, ELECTROPLATING SETS, AND ELECTROCHEMICAL BATTERIES