User guide

Elwe Didactic GmbH ▪ Steinfelsstr. 5 ▪ 08248 Klingenthal ▪ Germany ▪ www.elwedidactic.com

3B Scientific GmbH ▪ Rudorffweg 8 ▪ 21031 Hamburg ▪ Germany ▪ www.3bscientific.com

Subject to technical amendments

6.10 Polarisation

• Set up the polarisation grating (18) in the

screen holder.

• Check the reception when the polarisation

grating is aligned horizontally.

• Check the reception when the polarisation

grating is aligned vertically.

Conclusion: Since in one state a signal is received

but when the grating is rotated 90° no signal

reaches the receiver, it can be demonstrated that

the horn antenna produces a field that oscillates in

one direction only, i.e. the output is polarised.

The experiment proves that the waves are trans-

verse.

If the transmitter and receiver are set up so that

one is vertical and one horizontal, no reception is

possible

If the polarisation grating introduced into the

beam and tilted by 45°, an attenuated signal is

received. The polarising plane is thus inclined.

6.11 Transmission of information

• Set up the transmitter and receiver facing one

another.

• With the receiver off the rail, move it in a

plane perpendicular to the rail.

• Reception is best when the openings are facing

one another.

Using internal modulation (3 kHz signal) or exter-

nal modulation (e.g. sound from an MP3 player) it

is possible to transmit information.

Conclusion: microwaves (electro-magnetic waves)

can carry information.