GPSII GPS Satellite Controlled Clock
Here is the Cylindrical GPSII Clock. A total of ten were assembled.
The GPSII cylindrical enclosure was designed and manufactured by Mike
It is electrically the same as the acrylic boxed GPSII. The cylinder
is 4 inches in diameter. End caps are machined acrylic,
the tensioning rod and hardware are stainless steel. It is an amazing
item to look at. And very popular with celebrities.
GPSII is always accurate to within 500ns (nano-seconds) of the GPS Satellite
transmission -Far superior to local oscillator and AC line referenced clocks.
GPSII receives the satellite transmission using a compact "puck" style
1.5Ghz antenna. Indoor locations can provide adequate satellite reception
antenna is placed inside on a window sill. Some congested hi-rise environments
will require an external antenna mounting to achieve an adequate sky view.
The hi-gain active antenna includes magnetic base for easy mounting,
and is weatherproof. 10' of coaxial lead is included, and supports extensions
up to 50'.
GPSII incorporates a unique method of operation in areas with "spotty"
reception due to limited antenna mounting through use of a secondary time
In the event of satellite signal loss after successful startup; GPSII
will continue operation using the high precision 1pps signal pulse from
the GPS receiver.
The lower right colon lamp will extinguish to indicate the clock is
operating from the local precision, then relight when the satellite signal
has been restored.
If power is lost, a lithium battery will maintain GPS receiver ephemeris,
and quickly resume operation when power is restored. No typical
cold start TTFF
(Time To First Fix) delay is incurred when GPSII is re powered.
The initial startup acquire after installation may take 10-20 minutes,
Professionally engineered and skillfully handcrafted. Only the
finest components were used in the construction.
Though the term "rare" has been exhausted by others, the GPSII Cylinder
was built on special request only.
The clock is powered by a compact 12vdc wall adapter. The clock is fully
isolated from the line voltage.
Connections to 12vdc power and the GPS antenna are made at the side
of the clock.
The Oncore GT+ GPS receiver is visible at the upper back, mounted on
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