[Elecraft] OT: Changes at WWV, WWVB

[Hisashi T Fujinaka]

On Fri, 28 Nov 2014, Ken G Kopp wrote:

...

> Here's the most important info .... as of about a year
> ago the modulation scheme on WWVB (60 kHz) was
> changed (phase reversal each minute) and this has
> rendered most of the end-user equipment inoperative.
> Most (all ?) tracking receivers like the HP-117's are
> now useless without extensive modification.
>
> Most of the "atomic" clocks now in use ->do not<- synch
> to the current modulation scheme on the 60 kHz signal.
> This will explain the differences in displayed time on
> supposedly identical clocks and how some appear to
> not be getting sufficient enough signal to synchronize.

I heard from my time-nerd friends that the modulation scheme changes for
a short period at night to allow a chance for older equipment to sync
up. I don't know that for sure.

Technology Review said there are millions of pieces of equipment that
use the older scheme.

-- 
Hisashi T Fujinaka - htodd at twofifty.com
BSEE + BSChem + BAEnglish + MSCS + $2.50 = coffee