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PROCESSOR TECHNOLOGY CORPORATION
CUTS, COMPUTER USERS TAPE SYSTEM
APPENDIX IV
melts the rest of the joint will be hot enough for the solder
to "take", (i.e., form a capillary film).
(5) Apply solder for a second or two, then remove the solder and
keep the iron tip on the joint.
The rosin will bubble out.
Allow about three or four bubbles, but don't keep the tip
applied for more than ten seconds.
(6) Solder should follow the contours of the original joint.
A
blob or lump may well be a solder bridge, where enough solder
has been built upon one conductor to overflow and "take" on
the adjacent conductor.
Due to capillary action, these sol-
der bridges look very neat, but they are a constant source of
trouble when boards of a high trace density are being sol-
dered.
Inspect each integrated circuit and component after
soldering for bridges.
(7) To remove solder bridges, it is best to use a vacuum "solder
puller" if one is available.
If not, the bridge can be re-
heated with the iron and the excess solder "pulled" with the
tip along the printed circuit traces until the lump of solder
becomes thin enough to break the bridge.
Braid-type solder
remover, which causes the solder to "wick up" away from the
joint when applied to melted solder, may also be used.
INSTALLING AUGAT PINS
Augat pins are normally supplied on carriers (e.g., 8-pin and 16-pin
carriers).
In many cases the PC board layout permits Augat pins to
be installed while still attached to the carrier or a portion of the
carrier.
In other cases the pins must be installed singly.
To install two or more pins that are still attached to the carrier,
proceed as follows:
It is perfectly alright to appropriately
cut a carrier to accommodate the instal-
lation.
For example, an 8-pin carrier
can be cut in half (4 pins each) across
the short dimension to fit a 4-pin, 4-
corner layout.
It may also be cut in
half along the long dimension to fit a
4-pin, inline layout.
(1) Insert pins in the mounting holes from the front (component)
side of board.
(The carrier will hold the pins perpendicu-
lar to the board.)
(2) Solder all pins from back (solder) side of board so the sol-
der "wicks up" to the front side.
AIV-2
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