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KIT200 / KFDVKT202-05CP31 Rework Procedure
Purpose : Rework on the C383 overheated by R371 and replace with new 85C relay PCB.
Safety Precaution : Please disconnect the AC power cord before rework.
1) Remove panel screws (12pcs)
Pull out the Amp Module carefully from cabinet
2) Disconnect the wire harnessings attached to the amplifier as shown in below photos.
CN8
CN305
SPK2
Gnd 2
CN 306
Spkout
CN 201 CN 202
3) Remove 2x screws from relay board and pull up the relay board.
After Removal of the Relay Board
Screw Screw
4) Replace C383 / R370 / R371
a) Cut off the leads of the original C383 / R371 & R370 on component side of Amp board
b) Replace capacitor C383 from 50V 47uF 20% to 50V 10U 20% SHOEI 105
i Add Oil sleeve to the pins of new C383. Specification (ID=1MM L=10mm*2pcs)
ii Lap solder the new C383 (50V 10uF 105C) with same polarity as original shown on the PCB printing.
iii Add yellow glue to bond new C383 onto neigboring Big E-Cap or PCB Surface.
c) Replace resistor R371 from 300ohms/1W to 2W 1.5K 5% METAL OXIDE
i Add Oil sleeve to the pins of R371. Specification: ID=1MM L1=10mmL2=5mm
ii Lap solder the new R371 (2W 1k5ohm 5%)
d) Replace resistor R370 to a bare jumper wire or 0R0 link.
i Lap solder a jumper wire on R370
Before Change R370
After Change R371
R371
C383
R370
C383
Bond new C383 onto side of neighboring Big E-Cap
5) After completing step4, replace the New Relay board with +85C Relays and tighten up the screws.
New Relay board
Old Relay board
6) After replacing the New relay board, insert back all the connectors.
CN202 SPK2 Spkout(Red wire)
CN201
GND2(Red/black wire) GN306
GN305 GN8
7) Assemble back the amplifier and the rear panel.
w
8) General Operation Check for KIT-200
9) Packaging
Prepared by CK Wong
Date : Jan 07, 2006
Revision 01 : Item 4c / 4d are revised.