Panasonic KX-F900 Service Manual page 109

KX-F900
ADJUSTMENT ITEM
DESCRIPTION
(O)
20dB Electric Detection
(E)
MIC Input
(F)
Standard Frequency
EQUIPMENT
Marconi
SETUP Put in Receiver Test Mode.
RF GEN
FREQ 902.1000MHz
LEVEL 60dBIIV
SET MOD
FREQ 1.000kHz
LEVEL 5.000kHz
One end of BNC cable to left RF con-
nector, other end to Attenuator Input.
Audio Cable positive lead to isolation
capacitor, negative lead to GND, BNC
end to AF INPUT connector.
Oscilloscope
SETUP Xl probe connected to INPUT
1. Probe ground connected to GND.
TIME/DIV 1ms
VOLT/DIV 1V
Auto trigger
Attenuator
SETUP High Frequency Cable to
Attenuator Output.
Marconi
SETUP Put in Transmitter Test mode.
AF GEN
FREQ 1.000KHZ
LEVEL 41mV [23mV]
Connect High Frequency Cable to
right RF connector.
Connect Audio Cable positive lead to
MIC, negative lead to GND, BNC end
to AF GEN OUTPUT.
Marconi
SETUP Put in Transmitter Test mode.
AF GEN
FREQ f.000kHz
LEVEL 21mV
Connect High Frequency Cable to
right RF connector.
Connect Audio Cable positive lead to
MIC, negative lead to GND, BNC end
to AF GEN OUTPUT
PROCEDURE
On Marconi, press SINAD until the display shows
the SlNAD value and press dB. Then press RF GEN
and LEVEL. Attach the oscilloscope probe to 20dB
test point (TP7). Using the VARIABLE knob on the
Marconi, decrease RF GEN LEVEL until SlNAD v
alue is between 7dB and 9dB. NOTE: this value will
not be stable. Adjust VR401until oscilloscope voltage
toggles. This is the 20dB SET POINT.
NOTE: toggling may not occur at regular intervals.
Decrease RF GEN LEVEL until the SINAD value
decreases by at least 3dB. Check that oscilloscope
voltage is high. Now increase REF GEN LEVEL
until SlNAD value is at least 3dB above the 20dB
SET POINT. Check that oscilloscope voltage is low.
Adjust MR201 until Marconi MOD LEVEL
equals 5kHz +/-0.5kHz
Note
The 41mV value is for units of suffix A and
the 23mV value is for units of suffix B~.
Adjust VC401 until Marconi TX FREQ equals
926.100MHz +/-0.0005MHz
Note
This Item's setup is exactly the same as Item (E).
If you have done Item (E), simply look at TX FREQ
and make the adjustment.
,c,
Once aligned, please perform the following procedure.
1. Disconnect all equipment and solder connections. Use solder wick to clean up any solder you added.
2. Install the keypad membrane on top of the PORTABLE HANDSET keys.
3. Install the PORTABLE HANDSET P.C.Board.
4. Solder speaker wires back onto the P.C.Board observing correct polarity.
5. If you will align Item (E) RX Input in CORDLESS BASE UNIT, then solder a short wire across the MIC leads.
Remember to unsolder this wire after you completed the CORDLESS BASE UNIT alignment.
6. Insert antenna into the case.
7. Install antenna and top P.C.Board mounting screws and solder antenna connection.
8. Install case back and bottom mounting screws.
9. DO NOT INSTALL THE BATTERY AT THIS TIME!!!!H
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