[LEAPSECS] … a few seconds late

[Eric Scace]

   Shortwave broadcasters had additional reasons to modify the transmission time of pips to mark the top of the hour.

   For example, VOA’s transmitter site in Sao Tome is on local diesel generator-provided electricity. At times an AM broadcast band transmitter plus many (I don’t recall how many, but in the other of 6) transmitters were on the air, each running in AM at 50 – 250 kW power out.

   In the quiet period before the top of the hour, the impact of transitions between no-audio and a pip-at-full-modulation on the generator plant was significant. The generators belched smoke puffs for each pip, and power frequency and voltage levels jumped around. The solution was to stagger the pips a bit for each transmitter to smooth out the load on the generators.

> On 2019 Jan 04, at 03:24 , Richard Clark <rclark at lpl.arizona.edu> wrote:
> 
> Many years ago I recall hearing that the BBC used to advance their time
> signals on some shortwave services by ~200 ms to correct for the known
> deleys of the signals sent by their various transmitters.

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