Simulation diagram:
http://phet.colorado.edu/en/contributions/view/3572
Simulation:
http://phet.colorado.edu/en/simulation/circuit-construction-kit-ac-virtual-lab
Simulation of oscillative systems:
Elastic pendulum and simple pendulum
https://phet.colorado.edu/en/simulation/masses-and-springs
Simulation diagram:
http://phet.colorado.edu/en/contributions/view/3572
Simulation:
http://phet.colorado.edu/en/simulation/circuit-construction-kit-ac-virtual-lab
Simulation of oscillative systems:
Elastic pendulum and simple pendulum
https://phet.colorado.edu/en/simulation/masses-and-springs
Video on em spectrum
http://www.youtube.com/watch?v=kfS5Qn0wn2o
or
http://www.youtube.com/watch?v=snNwE6txxP0
or
http://www.teachersdomain.org/asset/phy03_vid_emspectrum/
Summary
http://www.bbc.co.uk/learningzone/clips/uses-of-electromagnetic-waves/10677.html
Em spectrum
http://www.teachersdomain.org/asset/phy03_img_lpaemspect/
Self-guided tour of the em spectrum
http://www.teachersdomain.org/asset/phy03_int_spectrum/
Interactive activity with different wavelengths
http://www.teachersdomain.org/asset/phy03_int_chandra/
Applet to show modulation (you must scroll down to see the applet and may then change various parameters
http://resonanceswavesandfields.blogspot.co.uk/20or.html
Waves. AM and FM modulation:
https://www.youtube.com/watch?v=-qyx8XV8dtE
What is modulation?
https://www.youtube.com/watch?v=yp2kjDSgko0
Advantages and disadvantages
http://www.diffen.com/difference/AM_vs_FM
or
www.wjec.co.uk/uploads/publications/8555.doc
Information on digital and analogue signals
https://www.tutorialspoint.com/digi_digital.html
The applet showing noisy digital signal. Work through the next few pages and the quick quiz at the end.
http://www.bbc.co.uk/schools/gcsebitesize/sciennrev3.shtml
Audacity (free program) may be downloaded from
http://audacity.sourceforge.net/
Simulation of analogue to digital conversion showing the effect of sampling frequency and bit number
http://www.vias.org/simulations/simusoft_adconversion.html
This video is about optic fibre:
http://www.youtube.com/watch?v=7h2xr-pi5VQ&safe=active
Coaxial cable:
http://www.youtube.com/watch?v=tERqorT2SqI&safe=active
Shielding cable:
http://www.youtube.com/watch?v=9uhobsHs-_o&feature=related&safe=active
http://www.youtube.com/watch?v=8yae=active
Video on satellites:
http://www.youtube.com/watch?v=vFypCugyFoM&safe=active
or
http://www.youtube.com/watch?v=J4gGalZV8TM&safe=active
or
http://www.youtube.com/w=active
Video on Marconi’s signal transmission:
http://www.youtube.com/watch?v=VM3JEUk6Q2s
An image of radio paths
http://www.windows2universe.org/spaceweather/images/radio_waves_paths.jpg |