Cordless Adjustment - Panasonic KX-F900 Service Manual

KX-F900
6. CORDLESS ADJUSTMENT
6-1. OBJECTIVE
This procedure will enable the technician to make adjustments to the KX-F900 PORTABLE HANDSET and CORDLESS
BASE UNIT.
_2. GENERALINFORMATION
This procedure has 2 sections. The first section instructs the technician on how to align the PORTABLE HANDSET. We
recommend aligning the PORTABLE HANDSET first, since you will need the PORTABLE HANDSET to align the
CORDLESS BASE UNIT. The second section aligns the CORDLESS BASE UNIT. You can use either section sepa-
rately, or together to align the entire cordless phone unit.
At the beginning of each section, you will find a preparation procedure instructing you on how to prepare the unit to the
point of placing the unit in TEST mode. Please follow this procedure to insure proper alignment.
Each section's procedure consists of Adjustment Items adjusting one specific variable hardware component.
Each Item lists the equipment needed, how to connect and setup the equipment, how to make the adjustment, and how
to verify the adjustment if necessary.
Before the actual procedure, you will find a procedure detailing how to place that part in TEST mode. You will have to
perform this procedure before each individual Adjustment Item.
Once aligned, please remove all equipment connections and solder points, and reassemble the unit. As a final check,
power up the phone and check for PORTABLE HANDSET linking with the CORDLESS BASE UNIT.
I PORTABLE HANDSET I
(1)PREPARATION
Please perform the following steps to prepare the PORTABLE HANDSET for alignment. Please refer to the
HANDSET REFERENCE DRAWING for connection and test point locations.
1. Remove battery cover and battery.
2. Remove both screws at the case bottom.
3. Grabbing hold of the back near the bottom, gently pry off the back of the case.
4. Remove the antenna mounting screw.
While heating the antenna solder connection, pull out the antenna. (Refer to page 125)
5. Remove the top P.C.Board mounting screw.
6. Unsolder both speaker connections on P.C.Board.
7. Remove the PORTABLE HANDSET P.C.Board.
8. Remove the keypad membrane.
9. Solder High Frequency Cable open end to ANT and RF GND points.
10. Using the Digital Multimeter, measure DC VOLTS output on the Telephone Analyzer.
Adjust the output voltage to 3.9V DC.
11. Solder battery connection wires at the points shown in the PORTABLE HANDSET REFERENCE DRAWING.
Solder the positive lead to IC204, towards the bottom of the P.C.Board. Solder the negative lead to the MIC
minus lead, closest to IC204. DO NOT APPLY POWER TO THE PORTABLE HANDSET AT THIS TIME!!!!!!
12. Solder a small, insulated piece of wire to GND as well.
13. Solder 1 isolation capacitor's positive lead to SP+ test point (TP4). When soldering, keep the lead close to
the P.C.Board as possible since you will lay the keypad membrane over part of this lead.
14. Solder a small, short, insulated wire to MIC test point (TP8).
15. Lay the keypad membrane over the keypad switch contacts.
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