3 ms·
Over-the-horizon radar uses HF to detect distant objects. See https://en.wikipedia.org/wiki/Over-the-horizon_radar https://en.wikipedia.org/wiki/Over-the-horizo
by bmurray7jhu 5y ago
Over-the-horizon radar uses HF to detect distant objects. See https://en.wikipedia.org/wiki/Over-the-horizon_radar https://en.wikipedia.org/wiki/Over-the-horizon_radar
- ellenhp 5y agoWith a big antenna array for beamforming, sure, you can do that. You absolutely cannot do over the horizon radar on 10 watts with two omnidirectional antennas though.
- jrockway 5y agoWait, who is doing WSPR at 10 watts? Most people are just using an unamplified IO pin off their Raspberry Pi or something; milliwatt at best. (It makes WSPR itself all the more impressive, however!)
- ellenhp 5y agoIf you have an SSB radio that you can hook up to a PC's sound card using VOX to activate the transmitter, you can use WSJT-X or similar software to do lots of digital modes like WSPR, PSK31, FT-8 and whatever's hot these days. I think best practice for WSPR is to keep power low though, so don't go crazy :)
- wglb 5y agoWhile there are a lot of folks using very low power on WSPR, there are also a lot on HF doing so with 100 watts, and even more in some cases.
- 8bitsrule 5y agoThe 'Russian woodpecker' and the US' OTH-B systems built decades ago used pulsed signals of 1 Million watts and up, with gigantic antenna arrays. [0] Comparison to WSPR is impossible (esp. given the complete lack of non hand-wavey details in the article). If the method were at all feasible, it'd very likely be commercially available). [0] https://fas.org/nuke/guide/usa/airdef/an-fps-118.htm https://fas.org/nuke/guide/usa/airdef/an-fps-118.htm