Yaesu FT DX 9000 CONTEST - 2, Техническое дополнение

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ALIGNMENT-1
Alignment
Introduction and Precautions
The following procedures cover adjustments that are
not normally required once the transceiver has left
the factory. However, if damage occurs and some
parts subsequently be replaced, realignment may be
required. If a sudden problem occurs during normal
operation, it is likely due to component failure; re-
alignment should not be done until after the faulty
component has been replaced.
We recommend that servicing be performed by au-
thorized Vertex Standard service technicians, expe-
rienced with the circuitry and fully equipped for re-
pair and alignment. If a fault is suspected, contact
the selling dealer for instructions regarding repair.
Authorized Vertex Standard service technicians have
the latest configuration information, and realign all
circuits and make complete performance checks to
ensure compliance with factory specifications after
repairs.
Those who do undertake any of the following align-
ments are cautioned to proceed at their own risk.
Problems caused by unauthorized attempts at re-
alignment are not covered by the warranty policy.
Also, Vertex Standard must reserve the right to
change circuits and alignment procedures in the in-
terest of improved performance, without notifying
owners.
Under no circumstances should any alignment be
attempted unless the normal function and operation
of the transceiver are clearly understood, the cause
of the malfunction has been clearly pinpointed and
any faulty components replaced, and the need for
realignment determined to be absolutely necessary.
The following test equipment (and thorough famil-
iarity with its correct use) is necessary for complete
realignment. Most steps do not require all of the
equipment listed, but the interactions of some ad-
justments may require that more complex adjust-
ments be performed in a sequence. Do not attempt
to perform only a single step unless it is clearly iso-
lated electrically from all other steps. Rather, have
all test equipment ready before beginning, and fol-
low all of the steps in a section in the order they are
presented.
Required Test Equipment
Digital DC Voltmeter (high-Z, 1 M-Ohm/V)
DC Ammeter
RF Millivoltmeter
AC Voltmeter
RF Standard Signal Generator w/calibrated out-
put and dB scale, 0 dBµ = 0.5µV
Signal Generator with calibrated output
Spectrum Analyzer good to at least 1 GHz.
Frequency Counter
50-Ohm Dummy Load (500 watts)
100-Ohm Dummy Load (500 watts)
150-Ohm Dummy Load (500 watts)
In-Line Wattmeter (500 watts, 50-Ohm)
Linear Detector
RF Coupler
Alignment Preparation & Precautions
A 50-ohm RF Dummy load and in-line wattmeter
must be connected to the main antenna jack in all
procedures that call for transmission, except where
specified otherwise. Correct alignment is not possi-
ble with an antenna.
After completing one step, read the following step
to determine whether the same test equipment will
be required. If not, remove the test equipment (ex-
cept dummy load and wattmeter, if connected) be-
fore proceeding.
Correct alignment requires that the ambient temper-
ature be the same as that of the transceiver and test
equipment, and that this temperature be held con-
stant between 68 °F ~ 86 °F (20 °C ~ 30 °C). When the
transceiver is brought into the shop from hot or cold
air, it should be allowed time to come to room tem-
perature before alignment.
Whenever 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 proce-
dure are based on 0 dBµ = 0.5 µV (closed cir-
cuit).