IFR COM-120C, Operation Manual

Page: 281 / 326

6 - 1 0 6
SECTION 6
OPTIONS
6-15-8 MPT 1327/MPT 1343 NUMBERING SCHEMES
A l l s i g n a l l i n g o v e r a i r u s e s M P T 1 3 2 7 n u m b e r i n g f o r t h e R U i d e n t i t y ( 7 b i t p r e f i x , 1 3 b i t
i d e n t i t y ) . H o w e v e r , m o s t R U ’s u s e M P T 1 3 4 3 n u m b e r i n g s c h e m e s t o r e d u c e t h e d i g i t s
d i a l e d t o t w o o r t h r e e d i g i t s f o r c a l l s w i t h i n f l e e t . T h e c o n v e r s i o n b e t w e e n 1 3 4 3
n u m b e r s a n d 1 3 2 7 i d e n t i t i e s i s p e r f o r m e d w i t h i n t h e R U . I t i s i m p o s s i b l e f o r t h e C O M -
1 2 0
C
t o d e t e r m i n e t h e M P T 1 3 4 3 n u m b e r ; h o w e v e r , t h e c o n v e r s i o n b e t w e e n t h e t w o i s
r e lat ively easy.
T o c o n v e r t M P T 1 3 4 3 t o M P T 1 3 2 7 :
M P T 1 3 2 7 P F I X = M P T 1 3 4 3 P F I X – 2 0 0
M P T 1 3 2 7 I D E N T = ( F L E E T I D – 2 0 0 0 )
x 2 + ( F L E E T N U M B E R - 2 0
o r 2 0 0 )
E x a m p l e :
M P T 1 3 4 3 I D = 2 0 1 2 5 0 0 2 7
M P T 1 3 2 7 P F I X = 2 0 1 - 2 0 0 = 0 0 1
M P T 1 3 2 7 I D E N T = ( 2 5 0 0 - 2 0 0 0 ) x 2 +
( 2 7 - 2 0 ) = 1 0 0 7