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MX421 Installation Manual
Introduction
This manual describes the operation and installation of the MX421 family of high-
precision GPS smart antennas.
The MX421 GPS and DGPS smart antennas were designed to work with the latest
Leica Control and Display Units (CDU) or other NMEA 0183 compatible navigation
devices. The MX421 can achieve position fix accuracies of better than 1 meter with
differential correction or better than 3 meters without correction.
Antenna models covered in this manual are:
MX421
- a GPS only smart antenna with an 8-pin power/data connector.
MX421B
- a combined GPS and Differential beacon smart antenna with an 8-pin
power/data connector. The beacon receiver operates in automatic mode
only.
MX421-10
- a GPS only smart antenna with a 10-pin power/data connector. This
antenna can accept differential corrections from an external beacon re-
ceiver. A 1 PPS timing output is optionally available.
MX421B-10
- a combined GPS and Differential beacon smart antenna with a 10-
pin power/data connector. The built-in beacon receiver operates in auto
mode.
MX421SB-10
- an enhanced MX421B-10 with a controllable built-in differential
beacon receiver. The built-in differential beacon receiver can be oper-
ated in either auto or manual mode when connected to an MX420 CDU.
These models use identical housing styles. To determine the particular model of
antenna you have, please check the number of connector pins and the model num-
ber inscribed on the serial number tag located at the underside of the antenna
housing and consult the section in this manual that refers to it.
Before installing the MX421, please read this manual carefully to ensure proper
installation and operation of the unit.
