VXA-120
Alignment
1
VXA-120 Alignment
Introduction
The VXA-120 is carefully aligned at the factory for the specified performance across the Aircraft
and Weather bands. Realignment should therefore not be necessary except in the event of a
component failure.
The following procedures cover the adjustments that are not normally required once the transceiver
has left the factory. However, if damage occurs and some parts subsequently are replaced,
realignment may be required. If a sudden problem occurs during normal operation, 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 authorized Yaesu service technicians who are
experienced with the circuitry and fully equipped for repair and alignment. If a fault is suspected,
contact the dealer from whom the transceiver was purchased for instructions regarding repair.
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 realignment determined to be absolutely
necessary. Problems caused by unauthorized attempts at realignment are not covered by the
warranty policy
Yaesu reserves the right to change circuits and alignment procedures, in the interest of improved
performance, without notifying owners.
The following test equipment (and familiarity with its use) is necessary for complete realignment.
While most steps do not require 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 signal step unless it is clearly isolated electrically from all other steps. Have all test
equipment ready before beginning, and follow all of the steps in a section in the order presented.
Correction of problems caused by misalignment resulting from use of improper test equipment is
not covered under the warranty policy.
Required Test Equipment
ο
Radio Tester with calibrated output level at 200 MHz
ο
In-line Wattmeter with 5% accuracy at 200 MHz
ο
50-
Ω
, 10-W RF Dummy Load
ο
Regulated DC Power Supply adjustable from 3 to 15 VDC, 2A
ο
Frequency Counter: ±0.2 ppm accuracy at 200 MHz
ο
AF Signal Generator
ο
AC Voltmeter
ο
DC Voltmeter: high impedance
ο
VHF Sampling Coupler
Alignment Preparation & Precautions
A 50-
Ω
RF 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 possible with
YAESU MUSEN CO., LTD.
FCC ID: K66VXA-120
EXHIBIT # 11
