PTU0 pages

Network Ready Portable Timing Unit
Model PTU
Model PTU Portable Time Unit – SPS C/A code version
The Portable Timing Unit (PTU) is low cost, battery operated, transportable
timing system that is designed to provide precise time of day at point of use.
The PTU may be automatically synchronized by means of either GPS signals,
or an serial time code such as IRIG B or Have Quick.
Operation of the unit can be monitored via an Ethernet interface, or by means
of front panel indicators and displays.
Outputs are 1PPS, Have Quick, IRIG B Time Code and Network Time
Protocol (NTP).
The unit is mounted in a rugged, weather proof case that may be easily
transported to the point of use.
When AC power is available, the PTU’s built-in power supply will automatically
charge the internal batteries.
Reference Input Sources
The PTU is extremely flexible in its ability to synchronize to a variety of timing
sources. Available references are:
16 channel GPS SPS receiver (standard)
12 channel GB-GRAM SAASM GPS receiver (optional)
IRIG B Time Code (standard)
HaveQuick/1PPS from external GPS receiver (standard)
Once synchronized to the selected reference, the PTU will use the reference to
continuously calibrate its internal oscillator so that accurate time can be
maintained in the absence the reference. Front panel LEDs indicate the
reference type in use, and whether time is valid. The PTU can be configured to
always use a particular reference source, or automatically select whatever
source is available.
Time Keeping
The internal time of the PTU is maintained by a high precision oscillator.
Selection of the oscillator type will determine the accuracy of the PTU when its
reference, (such as GPS) is not available. Available internal oscillator options
are
Temperature Compensated Crystal Oscillator (TCXO) -option
Oven Controlled Crystal Oscillator (OCXO) standard
Atomic Rubidium Oscillator - option
Network Interface
The PTU incorporates an Ethernet connection that provides a convenient
means of monitoring status of the instrument via a computer and simple web
browser. This interface is also used to provide NTP synchronization, firmware
updates and Browser based setup features.
Output Signals
The PTU provides a variety of timing signal outputs, giving maximum
application flexibility
1PPS 1 Pulse Per Second Signal Time Mark
Have Quick Time Code
IRIG B Time Code
NTP
Internal Battery Backup
The PTU contains an internal 7Ah battery that will operate the system in the
event prime power is lost. The battery charge is monitored and maintained
whenever prime power is applied to the PTU. Status is indicated by front panel
LED’s. Battery life is dependent upon the oscillator configuration selected and
the ambient temperature, but 5 hours is typical for the OCXO version.
Time Display
An 11 digit display indicates Years, Days, Hours, Minutes and Seconds. The
illumination of the display is controlled by a front panel switch to conserve
battery life.
External Event Input
The PTU includes an external event input that will latch the time of external
events applied as pulses to this input. The time tags are stored in an internal
memory and may be displayed and retrieved using the network interface.
Weatherproof Enclosure
The PTU is housed in a sturdy weatherproof enclosure that is suitable for
outdoor use in all weather conditions.
Typical Portable Timing Unit
Applications
Flight Test
Military Test Ranges
Portable Standby Clock
Aircraft Mission System Hot Start
Communications System Hot Start
1153 Warner Avenue . Tustin . CA . 92780 . USA
(714) 755 1050 . (714) 755 0175 (FAX) . www.brandywinecomm.com