TRC-424 4-Watt Solid-State
Transceiver (210-1522)     Hints and Tips             Faxback Doc. # 48947

NOISE

Your vehicle or boat can be the cause of much noise interference.  Since
the receiver section of your transceiver is very sensitive, it can pick up
even the smallest noise signal and amplify them.  Any noise that you hear
in the transceiver is almost totally from external sources.  The receiver
itself is exceptionally quiet.  Steady high noise levels can not be totally
eliminated by the internal Automatic Noise Limiter circuit (BLANKER).
Noise problems can not be solved internally (in the transceiver); they must
be solved at the source of the noise.

If you wonder if the noise is from your ignition system, the transceiver or
an external source, try this simple test.  Turn your ignition switch off
and set it to ACC (accessories).  This turns off the ignition, but supplies
power to the transceiver.  Most of the noise will disappear - indicating
that the source of the noise is your ignition system.

This interfering noise can be generated anywhere in the electrical system
of the vehicle or boat.  The first step in reducing or eliminating this
noise is to locate the source of the noise.

IGNITION SYSTEM

The most common source of noise is the ignition system.  This noise can be
identified by the fact that it varies with the speed of the engine.  It
consists of a series of popping sounds occurring at a regular rate that
will vary with the speed of the engine and stop when the ignition is turned
off.

There are a number of things that can be done to reduce this type of noise:

1.  Use only the 'radio suppression type' high voltage ignition wire.
    Most new cars come already equipped with this type of wire.

2.  Inspect the high voltage ignition wire and all connections made with
    this wire.  Old ignition wire may develop leakage, resulting in hash.

3.  If the noise still persists, replace the spark plugs with spark plugs
    that have suppressor resistors builtin.  Be sure to use the correct
    type for your vehicle.

Other sources of noise are:  generator/alternator, regulator, gauges and
static discharge.  Most of these types of noise can be effectively reduced
or eliminated by using bypass capacitors at the various output voltage
points.  We suggest that you check your RadioShack store for a wide
selection of noise reduction accessories.

SERVICE AND MAINTENANCE

Your transceiver has been built in accordance with RadioShack's exacting
quality control standards.  However, it should be treated with reasonable
care accorded any electronic equipment.  Avoid exposing it to severe shock,
dirt or moisture.

If you run into problems with the unit, we recommend you check the
following:

1.  If trouble is experienced with receiving.

    Check VOLUME On/Off switch setting.

    Be sure SQUELCH is adjusted properly.  Is it over-squelched?

    Check if the unit is switched to an operating channel.

2.  If trouble is experienced with transmitting.

    Be sure the Microphone is firmly connected to the Microphone jack on
    the unit.

    Check if the transmission line is securely connected to ANTenna Coax
    Connector.

    Check if the antenna is fully extended for proper operation.

    Are all transmission line connections secure and free of corrosion?

    Make sure you are fully depressing the push-to-talk button on
    Microphone.

    Check PA push-button setting.  It must be in 'out' position.

3.  If the transceiver is completely inoperative.

    Check the power cable and fuse (2A).

If these checks don't solve the trouble, do NOT attempt repair or
adjustments yourself.  The unit should be services only by a qualified
radio technician.  Whenever possible, return the unit to the store from
which it was purchased.

10-CODES

Citizen band radio operators have largely adopted the 10-code for standard
questions and answers.  Its use permits faster communications and better
intelligibility in noisy areas.  The following table lists some of the more
common codes and their meanings.

10-1    Receiving Poorly            10-10   Standing By
10-2    Receiving Well              10-13   Advise Road/Weather Conditions
10-3    Stop Transmitting           10-20   What is your location?
10-4    OK                          10-33   Emergency Traffic
10-7    Out of Service              10-36   Correct Time
10-8    In Service                  10-41   Switch to Channel
10-9    Repeat                      10-99   Cannot Copy You

WARNING

DO NOT OPEN UP THE TRANSCEIVER TO MAKE ANY INTERNAL ADJUSTMENTS.  Any
internal adjustments can be made only by (or under the direct supervision
of) a person holding an FCC 1st or 2nd Class Radio Operator's License.

Internal adjustments and/or modifications can lead to illegal operation as
defined by FCC Rules and Regulations, Part 95.  Such illegal operation can
lead to very serious consequences.

To Be Safe And Sure:

1.  You should never open up the case of your Transceiver.

2.  Never change or replace anything in your Transceiver.

(wr 08/04/98)