TriPoint VertexRSI 7200, Руководство по эксплуатации и обслуживанию

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7 2 0 0 A TP
6 - 1 3
3 3. Dr i ve the feed tube C C W to check that the feed tube w ill
back out of the soft li m i t. _______ (Check)
6.9 St e pt r ack T e sts
6.9.1 I nput S i gn a l V a ri a t i on
A ccurate track i ng i s pred i cated on a stab l e reference track i ng s i gna l . Therefore, the
stab ili ty of the track i ng s i gna l must be estab li shed before system track i ng accuracy
can be eva l uated.
Observe the beacon l eve l on the 7 2 0 0 d i sp l ay w i th the antenna parked at beam
center for at l east one m i nute and record the s i gna l var i at i on i n the fo ll o w i ng tab l e.
S i gna l V ar i at i on (dB)
If the observed var i at i on i s i n excess of + /- 0.1 dB, eva l uat i on of the system
track i ng accuracy w ill be uncerta i n, li m i ted by the amount of f l uctuat i on present.
6.9.2 T r ack i ng A cc u r ac y
1. In M a nu a l a nt e nn a c ont r o l , move the antenna off beam center i n the d i rect i on
li sted i n the fo ll o w i ng tab l e unt il the s i gna l l eve l drops 2dB.
2. A ct i vate St e pt r ack and a ll o w the system to repeak the antenna and record the
resu l t i ng s i gna l l eve l from the 7 2 0 0 A C U d i sp l ay be l o w i n the TRA C K LE V EL
co l umn.
3. Return to M a nu a l a nt e nn a c ont r o l and manua ll y peak the antenna and record
the resu l t i ng s i gna l l eve l i n the M A NU AL LE V EL co l umn. Repeat steps 1-3 for
each subsequent d i rect i on li sted i n the fo ll o w i ng tab l e.
D I R ECT I ON T R ACK L EVE L MANUA L L EVE L E RR O R
A Z C C W
A Z C W
EL UP
EL D O W N
NOTE: I f th e l e v e l ac h i e v e d i n St e pt r ack i s g r ea t e r th a n th a t
ac h i e v e d i n m a nu a l p eak i ng, e nt e r a z e r o fo r th e e rr o r .
4. C a l cu l ate the RMS track i ng accuracy as fo ll o w s:
RMS TRA C KIN G ERROR = [(A Z C C W) 2 + (A Z C W) 2 + (ELD O W N) 2 + (ELUP) 2 ] 1/2
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