SHORT WAVES

EQUIPMENT
    Short Wave Oscillator Demonstration Device
    LC Tuner
    Receiving Antenna


NARRATIVE
       The short wave oscillator is connected to a transformer which is plugged into 110 VAC. The waves produced by this transmitter are about 3.2 meters long.

    Standing Waves on a Transmission Line by Reflection
              Stretch the thin copper wires, which are wound on a spool, in front of the lecture table. Clamp the spool to a stand with a wooden clamp. Attached to the other end of the wires is a copper loop. Insert this into the hole provided in the base of the transmitter. Take the small bulb by the twisted copper wire and slide its base along the transmission wire to find the nodes and anti-nodes. The nodes are about 1.6 meters apart.

    LC Tuner
              A variable capacitor is connected to a loop which acts as an antenna and inductor. Connected across the loop is a flashlight bulb which lights at resonance. Bring the tuner near the transmitter (about 2.5 cm) and turn the capacitor dial until resonance is evident.

    Receiving Antenna
             Insert the 50 cm antenna rods into the holes provided on the transmitter loop. Insert a 79 cm antenna rod into each side of the plastic flashlight bulb holder forming an antenna. As the antennae are aligned and brought near (about 1 - 2 m), the flashlight bulb lights because an alternating current is produced in the receiving antenna.