VX-2500U Alignment, Page 1/4
Vertex Standard Co., Ltd.
VX-2500U Alignment
The VX-2500U has been carefully aligned at the factory for the specified performance across the
frequency range specified for each version.
Realignment should therefore not be necessary except in the event of a component failure, or alteration
of version. All component replacement and service should be performed only by an authorized Vertex
Standard 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 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 Vertex Standard service technicians
who are experienced with the circuitry and fully equipped for repair and alignment. Therefore, if a fault is
suspected, contact the dealer from whom the transceiver was purchased for instructions regarding
repair. Authorized Vertex Standard service technicians realign all circuits and make complete
performance checks to ensure compliance with factory specifications after replacing any faulty
components. 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, 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 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 familiarity with its correct use) is necessary for complete realignment.
Correction of problems caused by misalignment resulting from use of improper test equipment is not
covered under the warranty policy. 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 single 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.
Required Test Equipment
RF signal generator: calibrated output level at
1000MHz (0dBµ =1.0µV - closed circuit)
Deviation Meter (linear detector)
AF Millivoltmeter
SINAD Meter
Inline Wattmeter with 5% accuracy at 1000MHz
Regulated DC Power Supply: adjustable from 10 to 17 VDC, 15A
50-ohm Non-reactive Dummy Load: 100W at 1000MHz
Frequency Counter: >0.1ppm accuracy at 1000MHz
AF Signal Generator
DC Voltmeter: high impedance
RF Sampling Coupler (attenuation pad)
AF Dummy Load: 4
Ω
, 20W
Oscilloscope
Spectrum Analyzer
IBM PC/compatible computer
Vertex Standard VPL-1 programming cable and CE-** channel programming editor.
