There's plenty below 500kHZ... NDB and DGPS beacons, NAVTEX, experimental stations. Depending where you are you might catch some European broadcast stations. Check out others experience with different receivers though, many "general coverage" receivers will go low, but are relatively deaf below 500. As for antennas, if it's not amplified get as much wire out as practical, and away from noise if possible. Down on LF there's noise EVERYWHERE.
Hi Guys:
Longwave is fun, but to be honest, it's a lot harder than Shortwave. Noise is the killer here...there's way too much on the Longwave bands, and the seasons make a difference too (the longer nights in winter make longwave easier than the short summer nights we have now). European broadcast stations are possible on longwave here in Ontario, Canada, but you have to work at it...you'll need a very long wire antenna (mine is 150 feet, but I've heard of some that lay several thousand feet lol!) and a very sensitive receiver (I use a ham radio transceiver, which tunes all the way down to 50 khz).
Longwave broadcasts from Europe, Africa and Asia run from 153 khz to 279 khz, spaced by 9 khz intervals. They are extremely high powered to overcome atmospheric noise; some transmitters run 2 million watts or so! That being said, normally if I'm interested in trying longwave in the evening, I'll check out the fairly easy 162 khz from France...if it's audible, the band is open (as it is right now, actually...I can hear a thin French sound above the noise).
Here in Ontario I can receive longwave from
162 France, 171 Morocco, 183 Germany, 189 Iceland, 198 England, 216 Monte Carlo, 234 Luxembourg, and 252 Ireland. But again, conditions have to be good...a long winter night, low noise, that sort of thing. Have fun everybody and I hope you get lucky!
VA3SAJ