jotron TA-7650C - Page 83

Jotron AS| TR7750C: Operators Manual  ERROR CONDITIONS AND CORRECTIVE ACTIONS
Page 6-7
P/N: 84748 (pre_F)
LNA current
Unnormal current
consumption in the
LNA (Low Noise
Amplifier)
LO lock detect
Synthesizer is out
of lock
LO level
The LO level is
below 0dBm
RF module
RX alarm
Action:
Replace -
RX unit (LRU)
RF module (LRM)
Probable cause:
Defective
synthesizer circuits
/ VCO / TCXO
Action:
Replace -
RX unit (LRU)
RF module (LRM)
Probable cause:
Defective
synthesizer circuits
/ VCO / TCXO
Action:
Replace -
RX unit (LRU)
RF module (LRM)
Probable cause:
LNA transistor
broken because of
high RF input or
transient caused
by lightning.
IF current
Unnormal current
consumption in the
IF circuitry.
Action:
Replace -
RX unit (LRU)
RF module (LRM)
Probable cause:
Defective IF chip
on the RF board
Figure 6.2-2, Receiver RF module, errors and corrective actions