Standard Horizon Quest-X GX1500S, Руководство по обслуживанию

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11
Alignment
The GX1500S has been carefully aligned at the factory
for the specified performance across the marine band.
Realignment should therefore not be necessary except in
the event of a component failure. All component replace-
ment and service should be performed only by an autho-
rized Standard Horizon representative, or the warranty
policy may be voided.
The following procedures cover the sometimes critical and
tedious adjustments that are not normally required once
the transceiver has left the factory. However, if damage
occurs and some parts are replaced, realignment may be
required. If a sudden problem occurs during normal op-
eration, it is likely due to component failure; realignment
should not be done until after the faulty component has
been replaced.
We recommend that servicing be performed only by au-
thorized Standard Horizon service technicians who are
experienced with the circuitry and fully equipped for re-
pair and alignment. Therefore, if a fault is suspected, con-
tact the dealer from whom the transceiver was purchased
for instructions regarding repair. Authorized Standard
Horizon service technicians realign all circuits and make
complete performance checks to ensure compliance with
factory specifications after replacing any faulty compo-
nents.
Those who do undertake any of the following alignments
are cautioned to proceed at their own risk. Problems
caused by unauthorized attempts at realignment are not
covered by the warranty policy. Also, Standard Horizon,
a division of Vertex Standard must reserve the right to
change circuits and alignment procedures in the interest
of improved performance, without notifying owners.
Under no circumstances should any alignment be attempt-
ed unless the normal function and operation of the trans-
ceiver are clearly understood, the cause of the malfunc-
tion has been clearly pinpointed and any faulty compo-
nents replaced, and the need for realignment determined
to be absolutely necessary.
The following test equipment (and thorough familiarity
with its correct use) is necessary for complete realignment.
Correction of problems caused by misalignment result-
ing from use of improper test equipment is not covered
under the warranty policy. While most steps do not re-
quire all of the equipment listed, the interactions of some
adjustments may require that more complex adjustments
be performed afterwards. Do not attempt to perform only
a single step unless it is clearly isolated electrically from
all other steps. Have all test equipment ready before be-
ginning, and follow all of the steps in a section in the or-
der presented.
Required Test Equipment
RF Signal Generator with calibrated output level at
200 MHz
Deviation Meter (linear detector)
AF Millivoltmeter
SINAD Meter
Inline Wattmeter with 5% accuracy at 200 MHz
Regulated DC Power Supply: 13.8 VDC, 10A
50-ohm Non-reactive Dummy Load: 30W at 200 MHz
Frequency Counter: >0.1 ppm accuracy at 200 MHz
AF Signal Generator
DC Voltmeter: high impedance
VHF Sampling Coupler
AF Dummy Load: 4 Ohms, 10 W
Oscilloscope
Spectrum Analyzer
CP160 GPS/Chart Plotter
GX2360S Marine Transceiver
Alignment Preparation & Precautions
A dummy load and inline wattmeter must be connected
to the main antenna jack in all procedures that call for
transmission. Correct alignment is not possible with an
antenna.
After completing one step, read the following step to de-
termine whether the same test equipment will be required.
If not, remove the test equipment (except dummy load
and wattmeter, if connected) before proceeding.
Correct alignment requires that the ambient temperature
be the same as that of the transceiver and test equipment,
and that this temperature be held constant between 68 °F
and 86 °F (20 °C and 30 °C). When the transceiver is
brought into the shop from hot or cold air it should be
allowed some time for thermal equalization with the en-
vironment before alignment. If possible, alignments
should be made with oscillator shields and circuit boards
firmly affixed in place. Also, the test equipment must be
thoroughly warmed up before beginning.
Note : Signal levels in dB referred to in this procedure are
based on 0 dBµ = 0.5 µV (closed circuit).