Art Unwin wrote:
Centuries past there was a cold spell on Earth where it is stated
radiation propagation did not occur because of the lack of sun spot
observations. This period lasted about 30 years if my memory is
correct. ...
Art KB9MZ...xg

With "radio" being discovered in 1895 by Tesla:

http://www.pbs.org/tesla/ll/ll_whoradio.html

how many "centuries" are you talking about?; and, can you provide a
lead to this data you are referencing?

Regards,
JS

--
It is like a nightmare where the public servants are the people which
the police are supposed to protect us from!