Panasonic KX-F900 Service Manual page 88

F KX-F900
Check TX VCO voltage,
+B signal and VTX signal.
/
RF unit I NO
(+B = "high"?)
I
(VTX = "high"?)
YESi-'_
TX VCO voltage OK? I NO
I
TX VCO voltage
Base Unit: 1.3V_+O.5V
Handset: 1.3V_+O.5V
(page 87)
I Check signal line.
I
I
I Check TX VCO circuit.
[
I heck RST. SI, CPS
and LD signal lines.
L
-- - High level ....
Base Unit: Approx 5V
Handset: Approx 4V
Check TX VCO voltage.
I "° I
TX VCO voltage OK?
TX VCO voltage
Base Unit: 1.3V _+0.5V
Handset: 1.3V -+0.5V
(page 87)
I
Check TX VCO circuit. I
!
Check RST, Sl, CPS I
and LD signal lines.
I
[
I
Check RX VCO voltage and I
VRX signal.
I
F
RF unit
(VRX = "high"?)
YES_ "_
I I
RX VCO voltage OK?
/
YES I
TX VCO
voltage
Base Unit: 1.3V + 0.5V
Handset: 1.3V _+0.5V
(page 87)
NO
• Check VRX signal line. I
Check RX VCO circuit.
Check RST, SI, CPS
and LD signal lines.
1
-- High level--
Base Unit: Approx 5V
Handset: Approx 4V
-88-