I've only just started playing with the RTL-SDR USB dongle I bought and the freely available software that grabs the radio frequencies out in the
ether.
SDR = Software Defined Radio.
So far I have only picked up some FM radio stations locally, Some CB Radio traffic, and on my mobile using the dongle and a free app, I have been able
to watch and look at/map the info of the aircraft flying over towrds the nearest city's airport and the light planes cruising the adjacent coastline
doing some 'shark spotting'. It's a bit of cheap fun and the USB stick I bought cost $44AUS including postage. They range in the US from $10-300USD
and there is freely available software (with plug-ins) to do various decoding of digital signals (depending on what you are listening for).
Anyway, while looking on the linked website, I was seeing if there was any new apps/plugins to cover some extra digital signals to decode. I came
across this short article which showed one SDR users recording of interference he encountered from the arecibo observatory and the displayed
interference had part of the interference pattern that I had seen here on ATS related to weather radar maps showing circles of radiating spikes
associated with the HAARP array in Alaska.
The source link shows a youtube link of the interfence the user encountered while the researchers at the observatory heated the ionosphere by using
the telescope to pump 600 watts of radio energy into the ionosphere to heat it.
If you browse the linked website or search for SDR, or RTL-SDR, you should find a LOT of things these little USB sticks can pick up. eg: CB Radio;
Weather Maps downlinked from Satellites; Digital Radio/TV. The good thing with these Software defined Radios are that they do not have any radio
frequency bands blocked out (unlike some radio receivers).
I'm living in a tent (2+ years) so may not get to post much more, but I would love to see some feedback from ATS on the HAARP reference and if any
others are using SDR and what things they have found. These USB sticks would also be handy in differing future circumstances.