sunair RT-9000C, Руководство по эксплуатации и обслуживанию

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RT-9000C Hardware Supplement
Document No. 8128000602
Revision A (19 Mar 2007)
8-12
RT-9000 C
BITE (Built-In-Test-Equipment)
The BITE function is a monitoring function that runs continuously in the background and checks all three local
oscillator frequency outputs. Programmable logic part U202 performs the BITE function.
The PLL Controller used for both the First and Second Local Oscillator circuits produce lock-detect signals
when their respective control loops are locked. Under locked conditions, this signal will be normally a High
logic level with short (0.1
µ
s) low-going pulses. U202 checks the lock-detect signals from both PLL
Controllers to sense if either is Low for more than 0.8
µ
s, which would indicate a Fault condition.
The Third Local Oscillator / BFO output frequency is checked by a frequency counter function built in U202. If
the frequency counter finds the 455 kHz signal out of limits, this indicates a Fault condition.
U202 OR ties all three Fault status signals to produce a single SYN UNLOCKED signal. This Synthesizer
Unlocked signal passes to the radio CPU through card edge connector P1-pin 3.
8.3.1.3 Assembly Documentation
Synthesizer Assembly 1A2A2
Figure Document Page(s)
8.7 Parts List 8-13 & 8-14
8.8 Component Location Diagram 8-15
8.9 Schematic Diagram 8-16 through 8-21