Midland 70-1341, Service Manual

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SERVICING
70-1341/1344/1441/1444
COMPONENT REPLACEMENT
STATIC POTENTIALS
Many of the transceiver components are susceptible to higher voltages whether they are in or out of a circuit. Avoid
static or AC-line potentials when handling components and circuit boards. Prevent damage from electrically "hot" tips
that carry AC-line or static potential by using a grounded soldering iron. The only way to alleviate risk of component
damage from static discharge is to make sure all of the objects that touch the circuitry during component
replacement carry the same potential. Since the soldering iron is grounded, everything else must be grounded: the
bench, the equipment being worked on, and you. There usually isn't a need to wire yourself to your bench unless you
work on carpeting on dry-air days. Just touch bench ground when you sit down so that you and the grounded work
area are at the same potential.
REPLACING CHIP CAPACITORS AND RESISTORS
This section describes the best way to remove a chip component and install a new one. Chip components do not
have leads; they have metallic film on end-surfaces to solder to. Often the surface is tinned with solder. Because the
metallic film can be easily damaged by contamination and excessive heat, these components must be soldered very
carefully. No chip component can be unsoldered, then resoldered without damage. Always discard a used
component.

ITEMS REQUIRED:
Grounded temperature-controlled soldering iron with a 1/32 inch flat-blade tip. The tip temperature must be
maintained at approximately 600 degrees Fahrenheit.

60/40 electronics-grade solder, 22 gauge or thinner, with rosin flux.

Tweezers or longnose pliers.

Thin desoldering-wick.

Isopropyl alcohol or equivalent for solvent.

Rosin solder-flux. DO NOT USE ACID FLUX.

Procedure:
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