Unit installation

TECHNICAL DESCRIPTION INTRAC-305

The Basic algorithm available in the Rapid Model Generation

table is not of NORAD origin. It has none of the

embellishments found in the NORAD routines and is meant for

test purposes only.

Once the orbital model has been built using the ephemeris

data the INTRAC tracks the satellite from it and updates and

improves it over the following hours and days.

PROGRAM TRACK The IESS-412 and NORAD data can also be used by INTRAC

to calculate the satellite’s path which is then used for a simple

Program Track operation.

The selections available in Models - program Track are the

same as are available in Rapid Model Generate. On selecting

the required algorithm and pressing ENTER the INTRAC

enters Program Track mode.

Program Track is an open loop method of tracking and as such

is unable to correct for any transducer errors or distortions to

the antenna caused by wind.

RESERVE MODEL Once the orbital model has been built the INTRAC tracks the

satellite extremely accurately by continuously monitoring the

satellite’s position and updating the model. When the beacon

signal is not present INTRAC can still track accurately by

predicting the satellite’s position from the model. However if

the beacon signal is lost for more than 72hrs INTRAC deems

the model to be no longer valid. In such a situation INTRAC

can fall back to a Reserve Model. This is a Program Track

model built from either the IESS-412 or the NORAD data. The

selection is made in Models - Reserve Model. Assuming the

appropriated data has been loaded and is valid INTRAC will

automatically fall back to this model when it can no longer

predict accurately.

CLEAR MODELS The “Clear Models” menu is used to clear one or more of the

INTRAC Model, the IESS-412 Model or the NORAD model.

Clearing the INTRAC Model clears the current satellite model.

Selecting Auto Continue after this clearing will cause the

INTRAC to enter Learning Mode.

Clearing the IESS-412 or NORAD Models simply marks the

ephemeris data as being no longer valid. Selecting IESS-412

or NORAD for Rapid Model Generate or Program Track will

cause the menu to jump to the Edit IESS or NORAD data

menus for new data to be input. Also clearing the data will

mean that Reserve Model will not function.

ANTENNA MOTION LIMITS The INTRAC-305 has user setable software limits to confine

the antenna movement. If a limit is reached in an automatic

mode drive is inhibited, the INTRAC emters Standby Mode, a

primary alarm is raised and the System Alarm indicator is