User's Manual Part 2

T
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CAS / Part No. 9000000
SYSTEM DESCRIPTION AND INSTALLATION MANUAL
34-43-20
15 Feb 2003
Use or disclosure of information on this page is subject to the restrictions in the proprietary notice of this document.
4--18
Table 4--1. TT--950/951/952 T
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CAS Computer Unit Interface Description (cont)
Connector Pin
Designation
Functional Description
RBP--7D Audio Tone Enable Program Pin (NO)
If this programming pin is connected to program common, (RBP--7K), all voice
announcements are delayed by one second and are preceded by a tone. If pin is left
open, no delays or tones occur.
RBP--7E Ground Display Mode Program Pin (NO)
The T
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CAS computer unit monitors this programming pin to select the TCAS ground
display mode while the aircraft is on the ground. If the aircraft is on the ground and this
pin is connected to program common (RBP--7K), TCAS goes into standby mode. If this
pin is left open and the aircraft is on the ground, TCAS displays traffic only. Aural and
voice annunciations are inhibited while the aircraft is on the ground.
NOTE: TCAS does not display any traffic that it locates on the ground. TCAS aircraft
has WOW and intruder aircraft reports the same altitude or a lower altitude.
RBP--7F Display All Traffic Program Pin (NO)
The T
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CAS computer unit monitors this program pin to select either the all traffic display
mode or the TA/RA only mode. If this pin is open, all traffic is displayed. If this pin is
connected to program common (RBP--7K), the TCAS displays only TA/RA type intruders.
RBP--7G Cable Delay Signal Program Pin (NO)
The cable delay program pins (RBP--7G, RBP--7H, and RBP--7J) convey to the T
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CAS
computer unit the amount of delay differential between the top and bottom antenna
cables. Pin RBP--7G determines whether a time delay is added to the top or bottom. If
this pin is open, the time delay is added to the top. If this pin is ground (connected to
program pin RBP--7K), the time delay is added to the bottom. The cable delay logic is
given below . Program common for the cable delay program pins is RBP--7K.
RBP--7H RBP--7J Differential
(MSB) (LSB) Delay Adjustment
Open Open 0--50 nsec No Change
Open Ground 51--150 nsec Add 100 nsec delay
Ground Open 151--250 nsec Add 200 nsec delay
Ground Ground 251--350 nsec Add 300 nsec delay
RBP--7H Cable Delay MSB Program (NO)
See RBP--7G.
RBP--7J Cable Delay LSB Program Pin (NO)
See RBP--7G.
RBP--7K Program Common
This is the ground source for use with program pins.
RBP--8A
Thru
RBP--8D
Reserved Program Pins