Jim Lux wrote:
I should think that many hams have things that can measure 3 ns (1000mm
light time), particularly in a repetitive system. That's one cycle at
300 MHz, or 36 degrees at 30 MHz.

The referenced W8JI 3 nS "measurement" was the delay
in a 2' dia, 100 T, 10" long loading coil on 4 MHz,
i.e. 4.5 degrees.
--
73, Cecil http://www.w5dxp.com