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	                 FWT-100 Radiachromic Reader


The FWT-100 Radiachromic Reader is a computer controlled
densitometer designed to read the FWT-60-00 Radiachromic
Detectors.  The complete reader system consists of a computer
(IBM PC\XT\AT compatible), the reader head, an ADC card for
the computer, a cable to connect the head to the card, and
software.


Hardware Installation

ADC Board
Before installing the ADC board in the computer you need to
note the base address of the board.  If you have other
expansion cards in the computer you should also check that
the base address does not conflict with the address of the
other cards.  If necessary, the base address may be altered
by changing the DIP switch on the ADC card.

To determine the base address of the card examine the DIP
switch settings and the numbers printed on the board (not the
DIP switch numbering).  Table 1 gives the decimal and
hexadecimal values and the position of each switch for five
typical switch settings.  It is recommended that one of these
settings be used.  The card is originally set up with an
address of 0x300.

Note the base address of the card so that this may be
specified in the configuration file for the software.

NOTE: Since computers vary in style you should consult your
systems manual for details on installing an expansion card in
your computer.  If you purchased a complete system (including
computer) from Far West Technology the card is already
installed and set to address 0x300.

To install the board in the computer you should first make
sure that the computer is turned off and unplugged.  Next
open the case to allow access to the expansion slots.  Choose
an appropriate empty slot for the card.  Remove the retaining
bracket, being careful not to drop the screw in the computer.
Firmly insert the card in the slot and screw the bracket to
the chassis.  Replace the case.


Connecting the Head to the Card
Before connecting the head to the card you should make sure
that the computer is turned off.  Connect either end of the
supplied cable to the card and the other end to the reader
head (the two ends are interchangeable).  Securely fasten
them by tightening the screws on the connectors.


Lamp Replacement
The FWT-100 comes with a lamp installed and one spare lamp.
When the lamp burns out or becomes too dim you should replace
it.  To replace the lamp first remove the access cover by
unscrewing the black thumb screw on the back of the reader
head.  Remove the access cover and, from the bottom of the
reader, unscrew the black thumb screw which holds the lamp in
place.  Disconnect the lamp from the circuit board by pulling
the connector off the board.  Remove the lamp and discard it.
Insert the new lamp into the holder as far as it will go and
tighten the thumb screw just enough to prevent the lamp from
moving.  Do not overtighten the screw or you may damage the
lamp's housing.  Attach the lamp's connector to the circuit
board.  Screw the access cover back in place.


Holders
The FWT-100 comes with two holders, the film holder and the
neutral density filter holder, which has a wider slot than
the film holder.  To remove a holder unscrew the thumb-screw.
A spring will push the holder up as you unscrew the screw.
You may need to apply a little downward force on the body of
the holder to ease pressure.  To insert a holder, drop it
into the slot and press it down while screwing the screw in.
Make sure that the thumb screw is securely fastened and that
the holder is even with the block surrounding it.  If it is
not secured down completely the computer will not be able to
detect accurately that there is no film present in the holder.
Both of these holders may be taken apart to clean the inside
of the holder.





Software Installation
As with most software it is recommended that you make a
backup copy of the original disk and store the original in a
safe place.  Use the DOS DISKCOPY command to make a backup
copy.  First make sure you have a blank formatted disk
available.  Next, insert the original program disk into drive
A: and type DISCKCOPY A: A: at the DOS prompt.  (DISKCOPY.COM
should be in the path or the current directory.)  Follow the
prompts with regards to switching disks.

The next step is to make a working copy of the program.  The
working copy may be on a floppy disk or in a directory on a
hard disk.  It should contain three files: FWT100.EXE,
FWT100.CFG and FWT100.CAL.  The first is the executable
program, which may be placed in the current directory or in
a directory included in the PATH environment variable.  The
second is the configuration file and the last is calibration
information which will calculate absorbed dose based on net
optical density and thickness of the radiachromic detector.
These two files should be in the directory from which you
start the program.

NOTE:  The supplied FWT100.CAL file is only a sample to show
how such a file is set up (see below for details of how this
file is set up).  It should NOT be used for determining
actual absorbed dose.



Configuration File FWT100.CFG:
The configuration file FWT100.CFG is an ASCII text file.  It
should be modified using an ASCII text editor or the ASCII
mode (sometimes called non-document mode) of a word-
processing program.  This file contains the default values of
many parameters used by the program.  The following describes
the data included in this file and the order in which the data
should be specified.


Port Batch StartId Thk NormThk Wl UseDefBkg MeasurePost Prec

The parameters are:
  Port - Hexadecimal base address for the ADC card.
  Batch - Batch number of the film; this determines which
      calibration curve will be used to assign a dose.
  StartId - ID for the first dosimeter.
  Thk - Average thickness of the film being used.
  NormThk - The thickness to which net optical densities
      are normalized.
  Wl - Starting wavelength.  Specify 600 or 510.
  UseDefBkg - Non-zero integer if the default bkg should be
      used for the detectors.
  MeasurePost - Non-zero integer if the post-irradiation
      optical density is to be measured.
  Prec - An integer value greater than or equal to 0
      indicating how many decimal places should be used in
      reporting doses.

The entries must be separated by at least one space and the
parameters may be on more than one line. The Batch and
StartingId parameters are alphanumeric strings.  They may
contain any sequence of printable characters (spaces
excluded) and may have up to 10 characters each.

EXAMPLE:  The sample configuration file contains the line:

300 8W9 001 47.5 50.8 600 0 1 2

This indicates that the ADC board is at address 300
(hexadecimal), which is the factory setting.  The current
film is from batch 8W9 and the first dosimeter's number is
001.  The average thickness of the film currently being used
is 47.5 microns and is being normalized to 50.8 micron film
(the calibration data was normalized to 2 mil = 50.8 micron
film).  The program will start measuring on the 600 nm
wavelength and will not use the default background.  It will
measure post irradiation optical densities and will report
doses to two decimal places, such as 2.48.



Calibration File FWT100.CAL:
The calibration file FWT100.CAL is also an ASCII text file
and should be modified using an ASCII text editor or the non-
document mode of a word-processor.  This file contains
information pertaining to the calibration curve you develop
for the film.  See below for the data included in this file
and Table 2 for an explanation of the type of curves you can
specify for the calibration.

Each line of the calibration file should have the following
parameters:

   Wl CalibId Batch Bkg Min Max Eqn p0 p1 p2 p3 p4 p5

where
  Wl = Wavelength to which this calibration applies.
  CalibId = Calibration identification.
  Batch = Batch to which this calibration applies.
  Bkg = Default background optical density.
  Min = Minimum normalized specific optical density to which
      this calibration applies.
  Max = Maximum normalized specific optical density to which
      this calibration applies.
  Eqn = Type of equation the calibration uses (see Table 2).
      This is a single character.
  p0...p1 = The six parameters of the calibration curve.
      Note that all six parameters must be specified even if
      the curve takes less than six parameters (such as the
      power series).

EXAMPLE:  The sample FWT100.CAL file contains the data:

510 Sample 8W9 .055 .03 2.0 3 .05 .482 .2 2.27 .4 5.32
600 Sample 8W9 .060 .03 2.0 3 .3 ..338 .8 1.06 1.5 2.22

This indicates that there are two calibrations, one for 510
nm and the other for 600 nm, and that both are called Sample
and are for batch 8W9.  The default background for the 510
wavelength is 0.055 and for the 600 wavelength is 0.060.  The
calibration for both wavelengths is considered good for
normalized specific optical densities in the range 0.03 to
2.0 and both use 3-point Lagrangian interpolation.  The
remaining six numbers on both lines are the six parameters.
For the 3-point Lagrangian interpolation these parameters
represent three (SOD, dose) points of the calibration curve.

     Table 2 - Equations supported by the FWT100 program.


Equation    Single   Algebraic Representation
   type    Character
__________________________________________________________________

Power Series   L     p0 * SOD^p1
                       (NOTE: the parameters are typically
                        determined from a linear regression
                        of log(SOD) vs. log(dose)


Polynomial     P     p0 + p1 * SOD + p2 * SOD^2 + ... + p5 * SOD^5


Exponential    E     p0 * exp(p1 * SOD)


Interpolation  I          SOD - p0
(Linear)             p1 + --------  (p3-p1),
                           p2 - p0

                         where (p0, p1) = first (SOD, dose) pair
                           and (p2, p3) = second (SOD, dose) pair


3-point        3     (SOD-p2) (SOD-p4) p1   (SOD-p0) (SOD-p4) p3
Lagrangian           -------------------- + --------------------
Interpolation          (p0-p2) (p0-p4)        (p2-p0) (p2-p4)

                                (SOD-p0) (SOD-p2) p5
                              + --------------------
                                  (p4-p0) (p4-p2)

                        where (p0, p1), (p2, p3) and (p4, p5)
                        are three (SOD, dose) pairs

In these equations, SOD refes to the specific optical density
of the detector.  p0...p5 refer to the parameters of the
equation as they are to be specified in the calibration file
FWT100.CAL.



Running the FWT100 program:
To run the FWT100 program the executable file FWT100.EXE must
be in the current directory or in a directory specified in
the path command.  The configuration file FWT100.CFG must be
in the current directory.  The calibration file FWT100.CAL
should be in the current directory; if it is not, the program
will still run but it will not assign doses.  To start the
program type FWT100 from the DOS prompt.  There are several
command line options which may specified to override the
default values and the values in the configuration file.
These options include the following:

-istart_id  Sets the starting id for the detectors.
-xaddress   Hexadecimal address of the ADC card.
-daddress   Decimal address of the ADC card.
-b          Measure the background of the detectors.
-p          Measure the post-irradiation optical density.
-tthk       Set the default film thickness to thk.
-wwl        Set the starting wavelength to wl (510 or 600).
-f          Turns off film present detection.

The leading '-' and first letter are the command line
switches.  If the switch takes a parameter (such as thk) it
should immediately follow the first letter; there should not
be a space between the switch character and the parameter.


The software is menu driven with some options having hotkeys.
The options are listed below, grouped by the main menu
category.  To activate one of the main menus simply press
the first letter of the desired menu (e.g. 'F' for the file
menu).  Options within a menu are typically chosen by
pressing the highlighted letter of that option or by moving
the selection bar to the option and pressing the ENTER key.

FILE Menu

Load - Loads a previously saved file.  After loading a file
you are queried about what type of readings to take.

Save - Saves a file to disk.

Change Dir - Allows you to change the current working drive
and/or directory.

Print Data - Prints the data to a file or to the printer.
The default file is PRN which should direct the data to the
printer.

OS Shell - Shells from the program to DOS while keeping the
program and data loaded.

Quit - Exit the program.


EDIT Menu
Opens up an editing window for the current dosimeter (the
entry tagged on the left side of the screen by an inverse
video '>').  See Table 3 for a list of commands used in
editing.


           Table 3 - Input Field Editing Keys


          Key                  Action
          ---                  ------
        LeftArrow             cursor left
        RightArrow            cursor right
        UpArrow               cursor up
        DownArrow             cursor down
        Ctrl-LeftArrow        word left
        Ctrl-RightArrow       word right
        Tab                   field right
        Shift-Tab             field left
        Enter                 process field
        Ctrl-Enter            process all fields
        Decimal (.)           move to right side of decimal point
        Home                  beginning of field
        End                   end of field line / end of field
        Ctrl-Home             beginning of first field
        Ctrl-End              end of last field
        Ins                   toggle field insert mode
        Del                   delete character at cursor
        BackSpace             delete character left
        Ctrl-BackSpace        delete word left
        Ctrl-R                restore field to original contents
        Ctrl-T                delete word right
        Ctrl-U                delete to end of field
        Ctrl-Y                delete to end of last field
        Esc                   abort data entry (if Escape checking is on)

OPTIONS Menu

Neutral Density Filter Check - This option guides you through
an optical density check using the FWT-160 standard neutral
density filter set.  The results of this check are displayed
on the screen as well as being appended to the file
FILTERS.LOG in ASCII format.

Readings - Lets you specify the type of readings to be done.
These include:
  Background Readings - For reading background OD.
  Normal Final Readings - For reading the post-irradiation OD
     of the Radiachromic Detectors.  Choosing this option
     will also open a window requesting whether the
     background should be assigned a default value.  If a
     calibration exists for the proper batch then a dose will
     be calculated after the OD is read.
  Calibration Final Readings - Takes the post-irradiation OD
     for a calibration set.  This will prevent the program
     from calculating a dose for the dosimeter.


SETUP Menu

Zero Reader - The program automaticallly zeroes on a regular
basis, so this option should rarely be needed.  It is
provided for the instance where zero drift may occur without
detection (e.g. when in one of the menus or in the DOS shell
for an extended period of time).  This will zero the reader on
the current wavelength.  This option should be chosen only
when the film holder is empty.  This may be activated by
pressing 'Z' when reading optical densities.

Wavelength - This option lets you choose either the 510 nm or
the 600 nm wavelength for measuring optical densities.  This
may be activated by pressing 'W' when reading optical
densities.


Accepting an OD Reading

The optical density reading is automatically accepted after
about two seconds, unless the -f command line option was
chosen when running the program.  Additionally, pressing the
ENTER key or depressing the button on the reader head will
accept to current OD reading for the current detector.  The
current detector is indicated by an inverse video '>' on the
left side of the screen.  You may change the current detector
by using the UP ARROW and DOWN ARROW cursor keys to move to
the desired detector.  After an OD reading is accepted the
next detector will become the current detector.  If there is
no next detector then one will be created and assigned the
next sequential ID.  ID's are incremented 'odometer' style,
with 'z', 'Z' and '9' advancing to 'a', 'A' and '0',
respectively.  Thus 'AZ-9.z' would advance to 'BA-0.a'.


                  ROUTINE DOSE MEASUREMENTS
For routine dose measurements the following are the typical
steps which may be taken.

1. Make sure the reader head is connected to the computer and
that the computer is turned on.  Switch to the directory from
which you want to run the program and type FWT100 at the DOS
prompt.  Include any appropriate command line switches and
press ENTER.  The program should load and then take a few
seconds to initialize.  The current optical density is
displayed in large digits in the lower left corner of the
screen.  The data is displayed in the middle window.

2. Load an existing data file, if desired, by choosing the
File Load option.  A file selection window will open.  Use
the cursor keys to highlight the desired file, then press
ENTER.

3. If the wavelength is incorrect, change it by choosing the
Setup Wavelength option.  The current wavelength is displayed
on the screen to the right of the large OD display.

4. Make sure the reader is zeroed.  The large OD display may
fluctuate between + or - .001; this is normal.

5. Insert a dosimeter in the slot in the film holder.  Unless
the -f command line option was chosen, the read head will
beep after about 2-3 seconds, indicating that the OD reading
has been accepted for that dosimeter.  You may also press
the ENTER key or the button on the read head to accept a
reading (this is required if the -f command line optiom was
chosen).  Repeat this step for each dosimeter, periodically
checking the zero.  You should periodically save the data
(using the File Save option) to protect against loss of
readings.

6. When all dosimeters have been read the data may be saved
on disk or printed out.  These are the File Save and the File
Print options, respectively.

7. To terminate the reading session, exit the program using
the File Quit option or using the ALT-X hotkey.


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