TC-618/626 Service Manual
84
Receive Circuit
Start
No signal
received
The Rx circuit is
normally supplied?
Yes
No
Check the Rx
power supply
circuit .
The Rx SQL level is
correctly set?
Rx LED works
normally?
The Rx frequency is
correctly set?
The Rx signaling is
correctly set?
The speaker works
normally?
The audio amplifier
works normally?
The Volume Control
knob works normally?
P29 and P52 of base-band
processor ICU200 outputs
signals normally?
The demodulation
parts work normally?
The IF and mixer
circuits work normally?
The RF mixer circuit
works normally?
Change the Rx
frequency.
Change the Rx
SQL level.
Replace the Rx
LED D601.
Change the Rx
signaling .
Replace the
speaker .
Check the audio
amplifier circuit.
Replace the
Volume Control
knob .
Check the audio
processing
circuit .
Check and
replace CD300
and CF300 .
Check Q105,
U 200 (P12, P21)
and XF1.
Check the local
oscillator VCO
circuit and Q 501.
Check the BPF
circuit and Q500 .
Check the
antenna.
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
End
Yes
Yes
No
No
No
No
No
No
No
Содержание TC-618
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Страница 84: ...TC 618 626 Service Manual 83 Troubleshooting Flow Chart Transmit Circuit ...
Страница 86: ...TC 618 626 Service Manual 85 MCU ...
Страница 91: ...TC 618 626 Service Manual 90 TC 626 ...
Страница 95: ...TC 618 626 Service Manual 94 Packing TC 618 as the example ...
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