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VX9700
Check if there is any major difference referring
RF_IN fed up with CW signal
in low gain mode of PAM
LG Electronics Inc.
Start
Check pin2, 7 at U108
To Figure 4.2.2.6. Is it similar?
YES
Check pin1, 8 at U108 (Vcc)
whether it is higher than 3.4V.
YES
Check pin4 at U108 (PA _ON1)
whether it is higher than 2.2V.
YES
Check pin3 at U108 (PA _R1 )
whether it is lower than 2.2V.
YES
Replace U108
Checking Flow
Checking Flow
YES
NO
NO
NO
Waveform
Waveform
Figure 4.2.2.6
PAM circuit is OK. See next page
Check Vcc line
Check PA_ON1 line
Check PA_R1 line
RF_OUT
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