Northern Airborne Technology THxxx - Manual (Page 20)

Tac/Com Control Head Manual SM06 Rev. 4.10
1.4
Hardware Design Features & Considerations
1.4.1 General
The Dzus mounted Tac/Com control heads use extremely high quality components,
including sealed gold contact switches, gold contact connectors and fully masked,
conformal-coated FR4 flame retardant circuit boards. Each unit is fully temperature
cycled, life-tested, and then supported with a solid one-year warranty and extensive
field support to ensure the best possible customer satisfaction.
A wide range energy conversion power supply is used in the control head, allowing
operation from 16-33 Vdc, for nominal 28 Vdc systems. Panel lighting must be adjusted
to suit the specific application, and is normally supplied as natural colouration 28 Vdc
incandescent lighting. Options include blue/white or NVG lighting available in +5, +14
or +28 operating voltages.
For ease of service, integrated circuits are socketed where possible, allowing fast return
to service of failed control heads and quicker bench troubleshooting. Control head
software is easily updated for improved features or expanded capability by an internal
EPROM exchange. Internal interface cards are plug-in modules to facilitate quick
service exchange or upgrade.
Wherever possible, fully plug-compatible interconnects are provided for existing systems
replaced by Tac/Com controls, making retrofits and test flights both easy to accomplish
and inexpensive. Where it is not possible to directly accomplish this within the control
head itself, an adapter cable or plug replacement on an existing cable is used.
1.4.2 Display Filtering/Lighting Options
Current LED displays used in Tac/Com II control heads are green (first generation
Tac/Com I controls used a yellow display), with fully formed 5x7-pixel alphanumeric
characters. They have a large character height of 5 mm/0.2" and a very wide viewing
angle (>150 degrees) that provides good readability from virtually all cabin mounting
locations, including centre consoles such as in the Bell 412/212.
Several display filter/panel lighting options are provided with LED controls to give the
best visual presentation in different ambient lighting conditions. ‘Filter’ refers to the
DISPLAY colour and appearance and ‘Panel Lighting’ refers to the panel legend back
lighting colour & voltage.
See Section 1.6 Unit Nomenclature for complete option list details.
The backlighting for the control head (which includes the LCD display) can be run from a
dimmer separate from other cockpit controls if more adjustment over the LCD back lighting is
desired. This will permit both backlighting and contrast to be adjusted for the best presentation.
The LED display automatically dims (on current production units) to 50% intensity when voltage
is detected on the control head light bus. The LED display is adjustable in 7 steps via the
SELECT (+/-) switch, when the Bright +/Dim - screen is displayed.
Page 1-10 Jan 4, 2006
ENG-FORM: 800-0108.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.