7 May 2017

VLF tests continue

Experiments at VLF by amateurs continue with DK7FC leading those TXing on bands from 970Hz to 8270Hz. People as far away as Italy and the UK have been trying to receive these transmissions, some successfully.

Unlike commercial stations, these are amateurs using modest powers and "back yard" antennas. At one time people said, "we'll never get over the garden wall at VLF". Instead, signals are being received over hundreds and sometimes thousands of kilometres. I think in the past I have copied 5 different amateur VLF signals from as far away as Germany and the Czech Republic.

The secret is long integration periods, very narrow bandwidths and great stability. Casual listening will not work. Amateur VLF work requires care and dedication, quite different from reception of commercial VLF stations with huge powers and antennas.

No comments: