Haier HS-2190, Руководство по обслуживанию

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Replacement
Carefully insert the replacement IC in the circuit board.
Carefully bend each IC lead against the circuit foil pad and solder it.
Clean the soldered areas with a small wire-bristle brush.(It is not necessary to
reapply acrylic coating to the areas).
“Small-Signal” Discrete Transistor
Removal/Replacement
Remove the defective transistor by clipping its leads as close as possible to the
component body.
Bend into a “U” shape the end of each of three leads remaining on the circuit board.
Bend into a “U” shape the replacement transistor leads.
Connect the replacement transistor leads to the corresponding leads extending from
the circuit board and crimp the “U” with long nose pliers to insure metal to metal
contact then solder each connection.
Power Output, Transistor Device
Removal/Replacement
Heat and remove all solder from around the transistor leads.
Remove the heat sink mounting screw (if so equipped).
Carefully remove the transistor from the heat sink of the circuit board.
Insert new transistor in the circuit board.
Solder each transistor lead, and clip off excess lead.
Replace heat sink.
Diode Removal/Replacement
Remove defective diode by clipping its leads as close as possible to diode body.
Bend the two remaining leads perpendicularly to the circuit board.
Observing diode polarity, wrap each lead of the new diode round the corresponding
lead on the circuit board.
Securely crimp each connection and solder it.
Inspect (on the circuit board copper side) the solder joints of the two “original” leads.
If they are not shiny, reheat them and if necessary, apply additional solder.
Fuse and Conventional Resistor
Removal/Replacement
1. Clip each fuse or resistor lead at top of the circuit board hollow stake.
2. Securely crimp the leads of replacement component around notch at stake top.
3. Solder the connections
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