Behold, Michael A. Terrell signalled from keyed 4-1000A filament:

Gregg wrote:

SSB+Carrier is known as vestegial sideband and has an efficiency
somewhere between AM and SSB.

Vestigial sideband is used for the Visual signal in NTSC TV
transmission. The term "Vestigial" comes from the fact that part of the
lower sideband is transmitted to reduce the phase shift caused by the
tuned circuits used to remove most of the lower sideband. In the very
early days of TV they couldn't build accurate filters to remove the full
lower sideband without causing video problems, so a compromise was made
in allowing a small part of the lower sideband to be transmitted.

Hi Mike,

Quite true! However there were several SW broadcasters experimenting with
VSSB in order to free up the congested SW bands.

--
Gregg
*It's probably useful, even if it can't be SPICE'd*
http://geek.scorpiorising.ca