Even lower power success on 500kHz

This afternoon I fired up my 700mW 500kHz WSPR beacon and wet string antenna (ERP microwatts) and got 3 reports from G3XVL at 61kms. So, I tried putting a 6dB then a 10dB attenuator between the PA and the ATU. Even with a power from the PA of just 70mW (never mind what that would be as ERP from the antenna!) he still gave me a -25dB S/N report! These were the three reports in reverse order:

2009-09-14 14:42	G3XBM	0.503829	-25	1	JO02dg	0.001	G3XVL	JO02nb	61	112
2009-09-14 14:40	G3XBM	0.503827	-23	1	JO02dg	0.001	G3XVL	JO02nb	61	112
2009-09-14 14:36	G3XBM	0.503823	-18	1	JO02dg	0.001	G3XVL	JO02nb	61	112

This suggests that just 35mW from the PA would have been enough to span this distance, even with my tiny antenna and poor ground.

Electricity from trees?

A company called Voltree has some information on a system that generates electrical power from living trees. No, this is not a joke. See also the article on this in New Scientist magazine today.

Power levels are low, but the people involved believe there is enough energy to power monitoring systems and alert people of forest fires using energy derived from trees.