Mag loop aerial for the Den

[pwdrive]

I know very little about antennas and propagation so these may be daft questions.

What is so special about these loop antennas that gives them such good performance? How important is the amplifier? Is it dependent on modern transistors or could you design a valve circuit that interfaced well with such an antenna?

Here's an old film about the ionosphere and propagation Jeffrey, for those new to it and oldies that have forgotten (including me):

https://archive.org/details/effectsofthe...ropagation

And another one, there are at least two parts to this film, links to the others will be seen on the Utube page:

https://www.youtube.com/watch?v=7bDyA5t1ldU

Hope this is of some use.

Lawrence.