SAM-III Construction Manual
See last page for document and copyright information, File: SAM-III Magnetometer Construction.doc, Page 2
SAM and SAM-III
The primary differences between the SAM-II and SAM-III are:
1.
Added third sensor
2.
Added separate 78L05 voltage regulators for each of the three sensors
3.
Added four NAND gates (74HCT00N) for multiplexing the third sensor
4.
Eliminated one analog output (because of microprocessor I/O limitations) and changed output
op-amp to LM358. The output shows K-Index and not magnetic induction
5.
Replaced DIN connectors with pluggable screw terminal block headers
6.
Replaced keyboard switches with surface-mount types
7.
Added temperature sensor input (modifications no longer required)
8.
Slightly smaller controller PCB
9.
Replaced microprocessor firmware
A retrofit kit to convert existing SAM-II processor modules to 3-axis also is available. The modifications
require replacing the microprocessor firmware and installing a small daughter-board on the main PCB,
making hand-wired connection and, of course, hooking up a third sensor.
The latest versions of all existing application programs that were used with the SAM-II can be used with
the SAM-III except that SAM-III requires a new SAM_INI program. Software setup is provided in the
Software Setup Guide.
Building the SAM-III
If you build the SAM-III yourself: Before you start, you should first read through all manual sections and
then follow them in order during construction. This will greatly reduce the chances of error. If you
choose to build the SAM-III without following this manual, you do so at your own peril and greatly
increase your chances of failure.
If you purchased the build option (p/n BLD-1) with your SAM-III, the printed circuit boards (PCB) already
are assembled as described in sections II through XII of this manual and the completed PCBs have been
tested and burned-in for 72 hours. You should review sections II through XII and you also should read
Sect. XIII to familiarize yourself with the SAM-III display and keyboard. After that, go to section XIV for
installation of the display and PCBs in the optional enclosure (p/n EC-1). The remaining sections cover
sensor installation and additional hardware information.
NOTICE: All parts in the SAM-III Kit are new. However, the reclosable (ziplock) bags holding
the parts may be recycled. Your kit may include bags with extraneous writing or stickers on
them. Ignore any such markings.
