Jackson Labs LTE-Lite, User Manual

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© 2020 Jackson Labs Technologies, Inc. 3
LTE-Lite User Manual
Usage Instructions
2.1 Powering Up the Evaluation Board
The LTE-Lite Evaluation Board is essentially a plug-and-play product that only requires a power
source and a GPS antenna to be connected to start generating highly-accurate output frequency and
1PPS signals that are phase and frequency aligned to UTC (USNO) and thus allow NIST-tracability.
To use the Evaluation Board, simply plug in the power supply using the supplied USB cable, plug in
the antenna, and wait about 15 minutes typically for the GREEN “LOCK-OK” LED to light up to
indicate that the unit is locked to UTC with better than +/-250ns phase accuracy, and a frequency
accuracy of better than 1ppb has been achieved. The internal software will auto-configure and
auto-calibrate the unit without any user-interaction and the longer the unit runs the more accurate it
will become.
For units with a Timing GPS receiver, the unit will start an Auto Survey process to establish the
stationary antenna position as soon as power is applied, and this is indicated by the SURVEY LED on
the Evaluation Board. The Auto Survey process will take at least 2000 seconds to finish, at which
time the antenna position is stored in internal memory, and operation with 1 satellite is possible (4
sats are required for Mobile mode/non-Position-Hold operation).
The Evaluation Board is powered directly from the USB cable, and/or from an optional external 5V
DC source on the +5V header. The USB cable and the external 5V DC source may be connected at
the same time as they are diode-protected from one another. The current is typically less than 0.07A
at 5V. Connect a clean +5V power supply to the +5V header block if the USB cable is not going to be
used, or is plugged-in intermittently. See
Figure 2.3 for the proper polarity of the optional external
5V DC power connection. Reversing the polarity on the power connector will not damage the unit as
it is diode reverse-polarity protected.
When communicating to the unit through the USB cable, Windows Vista, Windows 7/8 and Linux
will auto-recognize the unit as a USB serial COM adaptor, and automatically assign a serial port to
the unit. Windows will automatically load the USB COM driver for the board, and may need to have
access to the Internet to download the latest driver from the Microsoft update website. The user can
verify the COM port that windows assigned to the unit under the Computer Management window
(right click on computer and press the “MANAGE” button under Windows 7, or go to Control
Panel/Computer Management). The unit should show up as a standard serial port adaptor under the
“Ports (COM& LPT)” Icon. Please note the COM port number, as it is required for the initialization
of application software.