Onkyo A-SV610PRO, Руководство по обслуживанию

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board’s copper traces. One word of caution, this technique takes some practice. You are
using a sharp razor knife that WILL cut the boards traces if you use too much force while
cutting through the IC’s pins. Check the board before you solder the new IC in place. It
is highly recommended that you
practice this method on some scrap boards before trying
it on a customers unit.
Wire removal method: Apply flux to the IC pins. Use desolder braid to remove as
much solder as possible from each pin. Thread fine stainless steel or enamel coated wire
under one row of pins. Secure one end of the wire on a nearby component (i.e. a large
Electrolytic capacitor). Starting at the loose end, heat each pin and pull wire
simultaneously. Pull the wire as close to the PCB as practical.
As the solder between the pin and pad melts, the wire will pop out and leave the pin
standing free of the pad. Repeat these steps for the other sides
.
Hot air desoldering tool: There are several types of hot air desoldering systems.
Desoldering tools range from the inexpensive portable “pyropen” type that uses butane
fuel and a catalytic burner to produce heat, to the sophisticated temperature controlled,
auto-timed, variable suction, multi-nozzle hot air systems that can cost you hundreds or
thousands of dollars.
If you are on a tight budget, a handy device to get the job done is the “pyropen” or hot air
torch. These hot air, butane fueled, catalytic burner devices can be purchased for under
$100.00. To use this type of hot air device you have to ignite the torch, and adjust the
temperature. After it warms up place the nozzle tip about ¾ to 1 inch above the legs of
the IC you wish to remove. Move the nozzle tip around the IC to uniformly heat the IC’s
legs until the solder liquefies. Once the solder has liquefied use a dental pick or similar
device to lift the IC away from the board. As with other methods described here, practice
removing IC’s from a scrap board to hone your technique before you work on a
customers unit.