Robert11 wrote:

All USB ?

If so, is all aero. HF 30 MHz always SSB ?

Except for hams, almost everything is USB. Hams are not because there were
no standards when they started. Many of them used the same US military
surplus radio as an exciter which needed to be mixed with another signal to
produce one that fell in a ham band. The result was when mixed below 10mHz,
the result was the lower sideband, when mixed above it was the upper.

So that became the standard used by hams, but there is no legal requirement
to use any particual sideband.

The exception to that rule is the 5mHz ham band which is limited to a small
number of fixed frequencies in USB. (US only).

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM