Panasonic KX-TC2105LBB, Service Manual

Page: 23 / 63

8.2. How to change the channel
8.3. Adjustment
Adjustment Items Test Mode Adjustment
Point
*Procedure Check or
Replace
Parts
(A) Battery Low
Confirmation
3ch Talk - 1. Adjust the power supply voltage to DC 3.60V and confirm so that the
reading of oscilloscope is High.
2. Adjust that power supply voltage to DC 3.40V and confirm so that the
reading of oscilloscope is Low.
IC801
(B) TX VCO
Adjustment
3ch Talk T803
•
Adjust T803 so that the reading of the Digital Voltmeter is 0.8 ± 0.3 V. IC801, X801,
T803, DV1
(C) RX VCO
Adjustment
3ch Talk T804
•
Adjust T804 so that the reading of the Digital Voltmeter is 1.0 ± 0.3 V. IC801, X801,
T804,C831
(D) TX Frequency
Confirmation
3ch Talk -
•
Confirm so that the reading of the frequency counter is 48.860MHz ±
700Hz.
IC801,
DPX1,
T802
(E) TX Power
Adjustment
3ch Talk T802
•
Adjust T802 so that the reading of the RF VTVM is more than -5dBm.
IC801, Q802,
Q804, T802,
DPX1
(F) RX Sensitivity
Confirmation
(2nd IF output)
3ch Talk T801 1. Apply -60dBm output from S.S.G. (modulation frequency 1KHz, dev.
0KHz).
2. Confirm 2nd IF output so that the reading of AF VTVM is the maximum
value(more than 20mV).
DPX1, T801,
CF801,
CF802
(G) Noise Squelch
Confirmation
3ch Talk - 1. Measure the S.S.G. output level when the noise squelch changes from
Low to High. (modulation frequency 1KHz, dev.3KHz)
2. Confirm that the S.S.G. output level is -100dBm.
IC801, DPX1
(H) Speaker
Output Level
Confirmation
3ch Talk - 1. Apply -60dBm output from S.S.G. (modulation frequency 1KHz, dev.
3KHz).
2. Confirm that the reading of AF VTVM is more than 30mV
(Distortion:less than 7%) (volume High)
IC801
(I) Mic Modulation
Factor
Confirmation
3ch Talk - 1. Apply a MIC signal (1KHz, 4mV at 600
Ω
load).
2. Confirmation so that the reading FM Deviation Meter is 2.2 ± 0.5KHz.
IC801, DV1
(J) Data
Modulation
Confirmation
3ch Talk -
•
Confirm for 4KHz ~ 7KHz FM Deviation Meter reading.
Q802, Q804,
T802, DV1,
DPX1
*: The connections of adjustment equipment are as shown in Adjustment Standard (Handset) (P.24).
S.S.G. Frequency: 43.82 MHz
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KX-TC2105LBB