Short Wave Listener: the Art of Listening
This is a nice database on line : to have updated informations on HF radio
Even if you don't have a receiver at home, you can listen anyway at:

One of the best personal web site about receiver test is:
SWL projects Ik2nbu are available with sketch, images and test video at the following Google Drive links
Ham Radio Life Style
Link to my Projects and Docs   Video SWL Testing IK2NBU
Antenna Active 8 Way Splitter HF Receivers Home Made Single Conversion Receiver
Home Made HF Receiver Matrix Analog Receiver and SDR Home Made
Expert 8 Way Splitter with Filters, Amplifier and Noise Killer I & Q receiver SDR at 10.7 IF
Basic Project for a Noise Cancelling Audio CAF Capacitive Active Filter Test LMF100
RX Balun Calculator and HF Comparison Test OM Directional Passive Loop Test
Differents Loop Antenna from 50 to 90 cm Diameter Test Comparison Loop an Mini-Whip
SWL Antenna Half Wave / tunable from 10 to 15 Mhz band Test Loop OM with Tecsun and Kenwood Receiver
Stereo AM sample Audio and SDR Images HF Filter for RX and Driver TX
IF 9 Mhz Home Made for Single Conversion HF Receiver Home Made AGC RX 9 Mhz
Diplexer for RX IF at 9 Mhz Home Made Tecsun PL660 with Home made Active Loop
Military Voltmeter Modification 2 conversion OL receiver AM 1 Radio 1350 KHZ with Loop indoor antenna
  Testing IF home made SDR and Icom R72 comparison
  Military Vintage OL Receiver testing after modifications