In the chart below are the reports for beacon “H” from various Western US receiving sites recorded during the 24-hour period of 24 September 2020.
On the header of the chart RX is the Maidenhead Grid Square Location of each receiving site, time (Z) in increments of 3 hours for each observation and RST from each receiving site is based on the (Z) time of observation. NIL? indicates the presents of “H” but the inability to accurately assign a proper RST.
RX 0000Z 0300Z 0600Z 0900Z 1200Z 1500Z 1800Z 2100Z
DM12 NIL 579 NIL 459 459 NIL NIL NIL
DM15 NIL NIL NIL 469 459 NIL NIL NIL
DM44 579 589 NIL 579 579 579 579 579
DN31 NIL? 569 569 569 569 NIL NIL NIL
DN10 NIL 559 449 459 459 NIL NIL NIL
CN90 NIL 549 NIL NIL NIL NIL NIL NIL
CM87 NIL 459 NIL NIL NIL NIL NIL NIL
DN26 NIL? 459 459 NIL NIL NIL NIL NIL
DN70 NIL NIL NIL NIL NIL NIL NIL NIL
DM61 NIL NIL NIL NIL NIL NIL NIL NIL
EM20 NIL NIL NIL NIL NIL NIL NIL NIL
EM79 NIL NIL NIL NIL NIL NIL NIL NIL
After looking at the 24-hour chart for a while, a guess would be “H” might be ground wave to DM44. Given the more or less constant signal over the 24-hour period, the exception of course is the time surrounding 0600Z, but during that time period a number of odd things happen with 4 MHz propagation.
Receiver KiwiSDR
Ant: 80m dipole at 15m
location: DM12