472kHz receive here last evening

I receive 472kHz via my transverter but on RX it is totally passive i.e. I receive directly on 472kHz on the FT817 through a series tuned circuit at 472kHz.  Last night, mid evening, 472kHz WSPR was quite busy (see below):

If anything, the FT817 is marginally deaf on 472kHz. This does not seem to be issue though as I seem to hear most of what's going. The "antenna" for the above was the short baseline earth-electrodes: one end is grounded in the flower bed with a 1m long earth rod, about 15m away, whilst in the shack the other connection is to the mains earth. The link back from the far electrode to the shack is 32 x 0.2mm PVC covered wire at a height of about 2m. I am lucky that my RX noise floor is low at this QTH.

On TX last night I was copied by 8 different stations with best DX last night G8HUH (250km). Best DX on the earth-electrode system (on TX with 5mW ERP) is DL-SWL (701km).