Hi All
I am not surprised that Laurie has been seen/heard on 73 khz in VE1.
I said in a message some months ago that 73 khz was suitable for a
transatlantic qso, under normal to good propagation conditions and with
the power we are permitted to use.
This therefore is not a surprised to me and in fact any LF frequency
given suitable propagation and modest power would work long haul.
High power is normally associated with LF for reliability  purposes and
one tends to think that it is a necessity for communications over long
distances but this is not true, especially for a radio amateur who only
wants an occasional qso and some excitement.
With a modest vertical 100 - 150 feet tower in the clear and top loaded,
a suitable ground radial system and modest power say 1 - 5w erp a lot
could be achieved on LF long haul.
I know at least 9 radio amateurs that have these facilities, only two so
far are active on LF.
One of these persons has 3 x 130 ft towers, and most of the others have
2 each in excess of 100 feet. Most of these amateurs are located in GI
land, there are probably quite a lot more high towers throughout Europe
that I do not know about and would be suitable for LF if the persons
were interested, but it appears that most are NOT. The uptake in LF
activities around Europe is very slow, and those best equipped with
suitable antenna masts and real estate are the LEAST interested.
73 de Mal/G3KEV