ATLANTEK 200 User manual

OPERATORS MANUAL FOR
MODEL 200
THERMAL RESPONSE TEST SYSTEM
Revised March 14, 2003

SYSTEM OVERVIEW
The ATLANTEK Model 200 thermal response test system is designed to provide thermal
response vs. print density for imaging on direct thermal or thermal transfer media. This
system is based on a special purpose ATLANTEK controller board which drives a standard
thermal printhead and a programmable stepping drive controller. The system includes
provision for mounting four standard performance thermal printheads. The system is
controlled from a personal computer with parameter programming accomplished from menu
driven software designed specifically for thermal response and performance characterizations.
For a given printhead and media type the primary factors which determine print quality are:
1) Printhead Substrate Temperature
2) Printhead Platen Pressure
3) Applied Dot Power or Voltage
4) Dot Pulse Duration(Ton)
5) Print Rate(Tcycle)
6) Dot Duty Cycle(% Dot) - Dots printed per line
The ATLANTEK system is designed to control and measure these parameters and to provide
results which not only produce the visual print data but which are stored in computer data files
and thus can be recalled and analyzed. The two key print timing parameters are Tcycle and
Ton. The difference between these two variables is Toff which represents the dot cooling time
between printed dot lines.
Tcycle = Ton + Toff
To provide meaningful test data Tcycle and SPEED must be related by the expression:
[ L / (SPEED X Tcycle) ] = 1
Where L is the amount of paper advance per dot line. In this system L is fixed at .125 mm
providing a square matrix. This is to avoid overlapping dot lines or creating spaces between
dot lines, either of which introduce error in the densitometer readings.
Thus the specification of SPEED implies a value of Tcycle. The parameter APPLIED DOT
POWER (P/DOT) is controlled by the applied VOLTAGE through the expression:
P/DOT = [ ( VOLTAGE - Vd )**2 / Rdot ]
where Vd and Rdot are parameters of the printhead. Thus the applied VOLTAGE determines
P/DOT.
The system, consists of four major components: the PRINT MECHANISM, the POWER
SUPPLY, the ATLANTEK controller board and a COMPUTER containing the SYSTEM
SOFTWARE.

PRINT MECHANISM
The print mechanism provides the capability to interchange printheads industry standard, 8
dot/mm printheads which have been selected by ATLANTEK in order to provide a good
representative cross section of competing thermal printheads. This will allow the printhead
itself to be treated as a control variable for evaluation purposes.
POWER SUPPLIES
The system power supply consists of two modules containing two separate supplies as follows:
1. Adjustable Printhead Supply
2. Motor and Logic Supply
ATLANTEK CONTROLLER BOARD
The control board provides the following functions:
1. Stepper Motor Control
2. Printhead Control
3. Data and Control Interface to Computer
The stepper controller is a high performance stepper drive designed to provide both a wide
range of paper speeds as well as smooth, precise incremental motion. The smallest
programmable step increment is 50% of the dot pitch at the 8 dot/mm resolution or 16 dots/mm
of position resolution. The motor drives themselves employ a combination of chopper drive and
half-stepping to insure smooth, resonance free motion over the full range of paper speeds.
The printhead temperature control allows the operating temperature of the printhead assembly to
be programmed as a variable parameter from ambient temperature to 50 degrees Centigrade.
The computer measures the temperature and based upon the test requirements instructs the
control board to heat or not heat the printhead. The control board also determines the dot pulse
duration (Ton) and manages the head strobing in accordance with the test requirements.
PC-AT OR COMPATIBLE
The computer resident system software provides for independent configuration of all variable
parameters, plus a data base designed to store all test results together with their specific
configurations. This software has been developed by ATLANTEK specifically for the
purpose of performing thermal response characterizations and is designed to work in close
conjunction with the PRINTHEAD I/O driver card to insure the data throughput requirements
associated with the high speed end of the thermal characterization spectrum. All data entry
and system operation will be performed via this software package which provides simple
parameter configuration menus to insure user friendly operation during system operation all
variables and data are passed from the computer to the control board where real time execution
takes place.

PLOTTING
Plots of the test results may be obtained through the use of the optional "TECH-GRAPH-PAD"
software. TECH-GRAPH-PAD is a powerful menu-driven software package whose features
include the following:
- Plotting single or multiple data files
- Support for various types of hard copy devices
Printers, Laser Printers, Pen Plotters
- User defined labels and comments
- Automatic or Manual scaling
- Curve fitting

GENERAL SPECIFICATIONS
PRINT MECHANISM
MAX. MEDIA SPEED...................................125 mm/sec.
MINIMUM STEP INCREMENT...................0.0625 mm
PRINTHEAD RESOLUTION........................8 dots/mm
TEST PRINTHEADS SUPPORTED.............Kyocera 8" Model KST-216-8MPD1
Kyocera 8" Model KJT-216-8MGF1
Rohm 8" Model KF2008-B1
Rohm 8" Model KE2008-C2
Ricoh 8" Model SH216-08FSH41
Ricoh 8" Model EH216-08FS41
Gulton 4" Model SMO-108-864
REAR PANEL CONFIGURATION
PARALLEL PRINTER INTERFACE CONNECTOR (To Host Computer)
POWER ON/OFF SWITCH
FUSE
AC POWER CONNECTOR (Three prong)
CONFIGURABLE TEST SYSTEM PARAMETERS
PRINTHEAD DOT SIZE AND RESOLUTION (Fixed by P/H).
PRINTHEAD OPERATING TEMPERATURE
PAPER SPEED (SYNC. WITH PRINTING)
APPLIED VOLTAGE (Front panel setting)
SIMULTANEOUS OR MULTIPLEX STROBING OF PRINTHEAD (Automatically Selected)
DOT PULSE DURATION (Ton)
TEST PATTERN SELECTION
MEDIA TYPE (Determined by User).
RIBBON TYPE (Determined by User).
HEADER WIDTH
IMAGE WIDTH

COMPUTER
IBM PC/AT or true compatible with the following configuration:
512K RAM minimum
12 Mhz Clock
20 Megabyte Hard Disk
1.2 M Floppy Disk
Standard Keyboard
Monochrome or Color System
Parallel Printer Port (2 required for plotting option)
Serial Port (2 required for automatic densitometer readings)
PRINTHEAD OPERATING TEMPERATURE:
The PRINTHEAD OPERATING TEMPERATURE is variable under program control from
ambient temperature to 50 degrees Centigrade.
TCYCLE: The TCYCLE is variable under program control from 1.00 mS to 25 mS in fixed
increments as shown in Tcycle menu.
DOT PULSE DURATION:
The DOT PULSE DURATION (Ton) is variable under program control from 10 microseconds to
2 milliseconds.
APPLIED VOLTAGE:
The APPLIED VOLTAGE is continuously variable from approximately 13 volts to 28 volts from
the printer front panel.
TEST PATTERN DESCRIPTIONS:
Within the Model 200 there are several operator selectable test patterns that may be chosen to run
for a desired test session. Test patterns that are included within the standard system configuration
are a Checkerboard pattern and a Walking One pattern. Other supported test patterns include a
Self-Generating Barcode module and a Pixel On/Off pattern. The Checkerboard patterns are
available in various sizes and densities and may be sequenced during a test session. This test
images allow an operator to study the effects of changing the dot duty cycle (number of heating
elements energized per dot line) as opposed to the electrical duty cycle. Available densities
range from 10% to 100% patterns in 10% increments.
With the Walking One pattern an operator will see a single element imaged per dot line.
The output pattern will appear as diagonal line drawn from upper left to lower right one dot size
in thickness. This pattern could be used to test the integrity of the dots across the printhead or
used to examine the shape of a single dot imaged on a particular substrate.

The optional Imported Test File feature allows the operator to enter a .PCX file that is converted
into the proper format to be printed. The PCXM2.exe application supplied needs to reside in the
same directory as RTEST.exe application file. Sample .PCX files are provided, 640.pcx is a
sample image file that can be printed on a Model 200 equipped with the KST- 48 printhead,
TP1.pcx is a sample image file capable of being printed using the KST-216 printhead. The .PCX
image file size is dependent upon the printhead installed, the KST-216 printhead requires a 800 X
600 pixel file with a 640 dpi resolution, the KST-48 printhead requires a 640 X 600 pixel file with
a 640 dpi resolution. In the case of KST-216 printhead the entire 800 X 600 file will be printed in
the center of the printhead. The conversion application requires a 640 pixel wide image
requirement for the KST-48 printhead but due to the fact that KST-48 is only 384 pixels(dots)
wide only the right side half of the 640 X 600 field is actually printed. In both cases it is important
that the .PCX file have a color depth of 2 colors (or bimodal).
The optional Self-Generating Barcode Module will allow an operator to print a CODE-39
or a UPC-A bar code in the "picket fence" or "ladder" directions using direct thermal or thermal
transfer printing techniques. Several densities of each bar code symbology are supported. The
highest densities of both, the CODE-39 and the UPC-A symbologies are printed beyond the
defined limits as specified by AIM and the UCC. However, they are included within the
MODEL 200 to represent possible future trends in bar code printing and may prove useful in
evaluating experimental media.
****** I M P O R T A N T ******
Due to the difference in total number of dots across the printhead, the GULTON 4"
printhead is not capable of printing the bar code images.
The optional Pixel On/Off Pattern is actually a collection of five different image patterns; a
100% dot pattern, one dot On/Off (picket fence and ladder), two dots On/Off (picket fence and
ladder). This pattern is very useful in evaluating the number of"voids" or amount of "blooming"
for a given test session. It is also ideal for studying the effects of dot history and adjacency.
It should be mentioned that the MODEL 200 employs an "overlapped" method of printing.
This is a result of having the printhead's heating element larger than an incremental motor
advance. Therefore, the imaged area in the ladder direction sections will be larger than the
unimaged area. Due to this narrow unimaged area and inaccuracies inherent in stepper
motors, the ladder direction 1 ON/OFF image may appear to be "banded" for some test
conditions.

INSTALLATION
THE ATLANTEK THERMAL RESPONSE TEST SYSTEM is interconnected to the computer
as follows:
1. Connect power cable to back of test controller and plug into standard 110 volt wall socket.
2. Connect the printer cable to the female 25 pin "D" style connector LPT1.
Note: In order to guarantee proper system operation, the test controller MUST be connected to
the LPT1: port of the computer.
3. Connect the 9 pin serial interface cable to the COM1: port of the host computer; the other end
of the cable should be plugged into the SERIAL INTERFACE connector located in the rear of the
test controller.
4. Connect the other end of the printer cable to the 36 pin connector on the rear of the test
controller.
5. Connect the sensor interface cable to the 15 pin female "D" style connector on the front of
the test controller labeled "SENSORS".
6. Connect the other end of the sensor interface cable to the 15 pin "D" style connector on the
rear of the mechanism.
7. Connect the motor cable to the 9 pin "D" style connector labeled "MOTOR" on the front of
the test controller.
8. Connect the other end of the motor cable to the 9 pin "D" style connector on the rear of the
mechanism.
9. Connect the printhead interface cable from the rear of the mechanism to the female 37 pin
"D" style connector on the front of the test controller labeled "DATA".
10. Connect the printhead power cable from the rear of the mechanism to the female 25 pin
"D" style connector on the front of the unit labeled "POWER".
11. Connect the printer cable from the line printer (plotter or laser printer) to the LPT2:
connector on the rear of the computer (used in the plotting option only).
12. Connect the densitometer to the serial port COM2: on the rear of the computer (used for
automatic densitometer input only).
** IMPORTANT ***
For proper system operation the test controller MUST be connected to the LPT1: connector
and the line printer (plotter, laser printer) MUST be connected to the LPT2: connector on the
rear of the computer.

POWERING UP THE TEST SYSTEM
Before applying power the voltage adjustment knob on the front panel of the printer should
be turned fully counter-clockwise. This ensures that the applied voltage is below the maximum
value recommended for the printhead.
NOTE: If the voltage adjustment knob is positioned near maximum, the over-voltage
protector may shut the printhead power supply off. To reset the supply turn the voltage down,
turn the system off, and after several seconds restart the system.
Apply power by turning on the switch on the left side of the back of the test controller and also
turning on the switch on the right side of the computer. It is a good idea at this point to press the
reset button on the right side of the test controller front panel to ensure synchronism between the
two CPU's.
LOADING THE MEDIA
The test system mechanism is designed to accept a variety print of media, both thermally
sensitive and thermal transfer receptor stock. The media path is determined somewhat by the
nature of the media under test and the configuration of the supply. When testing media
narrower than 8 inches the media should be attached to 8.5 inch paper backing, this prevents the
printhead from firing directly against the platen roller.
The media should be oriented such that the side to be printed on faces up as it passes between
the printhead and platen roller. Printhead pressure should be released by rotating the cam lever on
the right side of the head mounting mechanism. The media should be fed in from the back side
of the printer. If the media is wound on a core, mount the two appropriately sized core plugs
into the ends of the core, slide the mounting shaft through the center and insert the shaft into
the slots in the supply mounts at the rear of the mechanism. Core plugs are provided for 1, 1.5
and 2 inch cores. Be sure that the brush side of the back tension plate is in contact with the roll of
media.
Media may be fed to the platen in either of two paths depending on the amount of back tension
necessary to prevent the target media from wrinkling. For lighter tension, thread media under bar
"C", between printhead and platen, and finally under the tear bar. If the media tends to
wrinkle during printing, additional back tension may be necessary. This may be achieved by
threading the media over bar "A" prior going under bar "C".
For sheet feeding and for very thick media, the supply mount may be in the way. The supply
mounting brackets may be eliminated by removing the two screws holding them to the base plate.
If difficulty is encountered in threading the media the feed button on the front of the printer
may be pressed. This will cause the print roller to spin, assisting in the paper threading process.
Slide the paper to both center and align it with the printer. Apply printhead pressure by
turning the cam shaft lever to the down position.
Refer to APPENDIX A for a loading diagram.

LOADING THE THERMAL TRANSFER RIBBON
The test system mechanism is designed to accept a variety of thermal transfer ribbons. The
ribbon should always be center justified with respect to the printhead.
The ribbon should be oriented such that the side carrying the ink faces down as it passes between
the printhead and platen roller. Printhead pressure should be released by rotating the cam lever on
the right side of the head mounting mechanism. Slide the roll of ribbon onto the ribbon supply
shaft. Slide an empty core over the ribbon take-up shaft. This shaft is made to accept one inch
inside diameter cores. Feed the ribbon around bar "B", between the printhead and receptor
stock, around bar "D" and over to the empty take-up core. Tape the start of the ribbon to the
take-up core. Center the ribbon by adjusting the ribbon stop plate. Wind enough ribbon onto the
take-up core to both align the ribbon and remove wrinkles introduced in the threading process.
Apply printhead pressure by turning the cam shaft lever to the down position.
Refer to APPENDIX A for a loading diagram.
PRINTHEAD PRESSURE ADJUSTMENT AND MEASUREMENT
Located on the top of the printhead swivel block is an eyelet. This is provided to allow the
attachment of an external force gauge for printhead pressure measurement.
Lifting on the gauge until it just releases a piece of paper pinched between the between the
printhead and platen roller yields an approximate value for printhead pressure. This may be input
to the data file in the comments section.
Pressure may be adjusted by loosening the lock nut on the cam lift spring (on the rear of the
mechanism) and turning the adjustment nut to a new operating point. Compressing the spring
increases pressure and expanding the spring decreases pressure. Be sure to tighten the lock nut
after adjustment is complete.

TEST CONTROLLER FRONT PANEL CONTROLS
There are four controls on the front panel of the test controller.
Each is described as follows:
1. RESET - Performs a microprocessor hardware reset. This button is used to perform
re-synchronization of the test controller and the computer.
2. TEST - Prints a test pattern.(providing that the printhead voltage is within
printing limits and the printhead is in the down position.)
3. FEED - Feed advances the paper to the beginning of the next page.
4. VOLT ADJ. - Allows the adjustment of voltage applied to the printhead. The applied
voltage is displayed on the panel meter on the front of the printer as well
as on the upper right corner of the CRT.
****CAUTION****
******************************************************************
Be sure to keep the voltage applied to the printhead below the manufacturers
maximum rated voltage or printhead damage may result.
******************************************************************
CHANGING PRINTHEADS
Tools necessary: 1/8" Allen wrench, 9/16" thin open end wrench (approx. .1" thick)
Each printhead is supplied mounted on its own unique carrier plate which maintains proper dot
line alignment. The carrier plates should remain attached to the printhead.
*****************
****IMPORTANT****
*****************
******************************************************************
NEVER ATTEMPT PRINTHEAD REPLACEMENT WITH THE PRINTER
POWER ON !!!
******************************************************************

The printhead should first be electrically disconnected from the printer by removing the
printhead interface and printhead power connectors on the left side panel of the mechanism.
Release printhead pressure by rotating the head lift cam shaft to the up position. Remove the
screw in the hole at the front of the printhead swivel block. The entire printhead assembly may
now be slid toward the right and removed from the mechanism.
Installation of the new printhead is accomplished by simply reversing the removal procedure.
NOTE: If the head lift mechanism is not fully lowered during a test, the system will sense that
the printhead is raised and the sheet will feed without the head being energized. This will
result in a blank sheet.
TEST SYSTEM OPERATION
The test system has been configured to be as user friendly and menu driven as possible.
The first message which appears on the CRT gives the system title and asks the user to strike
the Enter key on the keyboard to continue.
At this point the system software attempts to verify the presence of a valid media in the "A:"
drive that will be used as a source and destination for all data files.
Following this initialization process, the main system menu is displayed. All menu selections
may be chosen via the function keys F1 - F10. Available functions at this point may be
summarized as follows:
F1 - EXECUTE TEST - Allows the loading of print parameters as defined by either default
values or a previous test. Any parameter may be altered by the user after choosing this option.
Loaded parameter values are displayed in this menu. Following the test, the operator is
given the opportunity to enter several lines of comments regarding the test just executed and also
densitometer readings.
F2 - SINGLE PATTERN TEST - Allows the loading of print parameters as defined by
either default values or a previous test. Any parameter may be altered by the user after choosing
this option. Loaded parameter values are displayed in this menu. Only a single test pattern
section is printed for a defined test session. No SEQUENCING is allowed with this option.
F3 - TEST FILE EDITOR - Allows for the display of comments associated with any chosen
test with the capability of making any desired changes. Followed by a display of comments
associated with any chosen test with the capability of making any desired changes to
comments or density readings.
F4 - DIRECTORY OF TEST FILES - This selection displays a list of all previously performed
tests.
F5 - VIEW A TEST FILE - Displays a list of all parameters as well as comments and
densitometer readings associated with any operator selected test.

F6 - VIEW DEFAULT PARAMETERS - Lists the default parameters of the presently installed
printhead, including the maximum voltage level recommended by the manufacturer for a
nominal resistance printhead.
F7 - INVOKE PLOT UTILITY - Executes the TECH-GRAPH-PAD program to allow the
generation of dynamic sensitivity curves without terminating the MODEL 200 operating
system software.
F8 - CONFIGURE TEST SYSTEM - Enables/disables the SAMPLE mode option. When in
SAMPLE mode, the test sessions are not saved in a file therefore the operator is not prompted for
a file name.
F10 - EXIT FROM TESTER - Allows the operator to leave the test system environment and
return to DOS
NOTE:
TEST file names MUST conform to the following rules:
- At least one character long, but less than eight characters in length.
File names may ONLY be made up from the following characters:
- The letters A - Z, and a - z
- The numbers 0 - 9
- The following special characters:
( ) { } @ # $ % ^ & ! - _ ' ~
Any attempt to create a file that is outside this guideline will prompt the "ILLEGAL FILE
NAME" error message to appear.

SAMPLE OF THE TEST MENU TEST MENU
Head Type: Rohm2
File Name: TEST1
Printhead Set Temperature: 35
Image Width: Full
Choose from: current values
F1 - Reset to default values
F2 - Pattern type 50%
F3 - Dot pulse Duration (Ton) Seq up to 0.50 msec
F4 - Cycle Time (Tcycle) 5.0 ms
F5 - Media Type ATL-693
F6 - Head Heating(ON/OFF) ON
F7 - Wait for Temperature NO
F8 - Configure Output Image
F9 - Do the Above Defined Test
F10 - Exit to Main Menu - caution choices will not be saved
USING FUNCTION KEYS
Choosing F2,F3,F4,F6 or F8 results in a request to input an appropriate value and a return to
the TEST EDITOR MENU.
Parameter sequencing may be selected for choices F2,F3, or F4. This choice produces ten
samples down the page with the first sample printed at 10% of the final value, the second at
20% and so on down the page. Sequencing of a test pattern is only available when the
Checker board pattern is selected.
Changing the desired Test pattern is done by selecting the F2 option and choosing one of the
supported test patterns from the displayed Menu.
Selecting the F8 option (Configure Output Image) from the TEST MENU will allow an
operator to alter the image header width or change the test patterns image width.
NOTE: The following conditions automatically invoke the REDUCED printing mode.
- Pattern Sequence tests
- Hi Speed TCYCLE Sequence
- Any test session where the defined TCYCLE value is less than 2.0 msec.
Also, due to differences in the construction of thermal printheads for various manufactures,
the width of the REDUCED print area is not the same for all printheads.
For Example: Reduced print width
Kyocera KST-216-8MPD1 4 inches
Rohm KF-2008-B1 2.66 inches

ENTERING DENSITOMETER DATA
Following a test, The operator is given the opportunity to enter optical density either manually,
automatically, or not at all. If either the manual or automatic choice is selected, the operator is
given a choice on the number of densitometer readings to average before recording the value and
prompting for a PLOT value.
Manual entry is accomplished by simply entering the density readings at the keyboard
followed by the optional PLOT value.
Automatic density readings are done by reading the densitometer via a serial interface. Before
capturing density readings the operator must have connected the densitometer to the COM1: port
of the computer through a serial cable and had calibrated the densitometer. Once
initialized, density readings may automatically be transferred to the computer by closing the
densitometer over the target area, releasing it to its normally open position, and then depressing
the transmit button located at the top of the reader. An audio "beep" will be heard after the
computer has received the data from the densitometer. Plot values are entered through the
keyboard after the desired number of density samples are entered.
CREATING A PLOT
To create a plot the operator may invoke the Plotting software by selecting the F7 (Invoke
PLOT Utility) option from the MAIN MENU or the Tech-Graph-Pad program can be used from
outside the MODEL 200 operating environment. TECH-GRAPH-PAD is started from DOS by
entering "TGP" followed by a carriage return. Once started, an entry screen is displayed, and
the Main Menu appears. Several templates of plot files have already been created by
ATLANTEK to simplify creating test plots. These templates contain a variety of information
related to labeling the plots and scaling the data. Therefore the operator must select the
"Recall a Graph" rather than the "Create a New Graph" choice. Menu options are selected by
pressing the arrow keys on the keyboard until this choice is highlighted. When highlighted,
the operator presses the carriage return to invoke the selection. From the "Recall a Graph" menu
the operator selects the "Recall an Attribute File" option. The operator must now select an
attribute file to load the previously defined template information. A listing of available
attribute files can be seen by pressing the F9 key. The attribute to be loaded depends on
the test file to be plotted. Refer to the list below to determine the correct attribute file to load
for the current data file.
SEQUENCED VARIABLE ATTRIBUTE FILE
PATTERN PATTERN.ATB
Tcycle SPEED.ATB
Ton ENERGY.ATB

An attribute file is selected by moving the highlighted area to the desired choice and pressing the
return key.
After the attribute file has been selected the operator enters the name of the data file to plot by
selecting the "Data Files to Use" option from the "Graph Building Menu". The operator enters
the name of the data file by overwriting the asterisk's in the data files area of the second entry.
NOTE: The operator must delete any unused asterisk's from the file name prior to pressing the
return key. Failure to do this will cause the TGP software to attempt to read an incorrect data
file.
Once the data file has been correctly entered, the software automatically returns to the "Graph
Building Menu" from which the operator will choose the "Scaling" option and invoke
Automatic scaling. Selecting the "Output" option will now produce a plot of the current data file
that may be created on the computer's monitor screen or output to the line printer.
REDUCED WIDTH PRINTING
For test conditions where higher print speeds are required the MODEL 200 dynamically
adjusts amount of data printed across the printhead. This adjustment is necessary due to the
effects of having multiple strobes energized simultaneously and the percentage of dots
loaded during one dot line. All tests executed with a cycle time less than 2.0 milliseconds
and all pattern sequences are automatically printed in a reduced mode.
The test controller hardware connects the printhead strobes in pairs. A printhead having 8
strobe inputs is controlled by 4 lines to the processor. Similarly a 6 strobe printhead is
controlled by 3 independent strobe lines. This allows the current load to be distributed
over the cycle time and reduces the effects of voltage drops in the power planes within the
printhead. .page
For tests conducted using low density print patterns. All off the strobe lines are activated
simultaneously, however as the print density increases the strobes need to be activated in a
consecutively. This obviously increases the amount of cycle time consumed for actual
printing. In order to accommodate high density print patterns and maintain low cycle times the
number of head strobes is automatically reduced to 2 (2 pairs) in the case of 8 strobe heads or 1
(1 pair) in the case of 6 strobe heads. This will yield printing over the center portion of the
media and have wide blank margins along each side.
HIGH DENSITY PRINTING
As discussed in the REDUCED WIDTH PRINTING section, the printhead strobes are connected
in pairs. This is actually a violation of the printhead manufacturers recommendations for the
quantity of dots simultaneously energized during high density pattern printing. This
specification violation in no way harms the printhead, it does however cause a greater than
desirable voltage drop in the power planes within the printhead. This limits the actual energy
delivered to the individual dots during strobing and results in a lighter than expected printout
for a given set of parameters. For tests conducted using greater than 50 percent patterns,
densitometer measurements should be compared on a relative basis rather than considered
absolute.

PRINTHEAD PARAMETERS
Average resistance values of printheads supplied with system serial number ______________
MANUFACTURER MODEL
Kyocera 8" Model KST-216-8MPD1
Kyocera 8" Model KJT-216-8MGF1
Ricoh 8" Model SH216-08FSH41
Ricoh 8" Model EH216-08FS41
Rohm 8" Model KF2008-B1
Rohm 8" Model KE2008-C2

APPENDIX A
DIAGRAM FOR LOADING PAPER AND RIBBON

APPENDIX B
TEST SAMPLES

APPENDIX C
MAXIMUM OPERATING CONDITIONS GRAPH FOR KYOCERA KST-216-8MPD1 THERMAL
PRINT HEAD
EXAMPLE
For a test with the following conditions:
Ton=Sequence up to .5 milliseconds
Tcycle=5.0 milliseconds
Ton/Tcycle=.5/5.0=10%
From the graph, the maximum allowed power level is the point read on the Y axis where 10% on
the X axis meets the Ton curve for .5 milliseconds. This is approximately 0.75 watts.
From this power level the maximum allowed applied voltage is calculated as follows:
Vi= (Pi-0.04)Ra + 1.07
where
Vi is the maximum allowed applied voltage
Pi is the maximum allowed power level
Ra is the average dot resistance printed on the label on the front of the printhead (549 ohms for
this example)
Vi= (0.75-0.04)549 +1.07
Vi=20.8 volts maximum