VX-2500U Alignment, Page 2/4
Vertex Standard Co., Ltd.
Alignment Preparation & Precautions
A dummy load and inline 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 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 (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 20 and 30°C (68 and 86°F). When the
transceiver is brought into the shop from hot or cold air it should be allowed some time for thermal
equalization with the environment 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.
Before beginning, connect the transceiver and PC using the VPL-1 programming cable as described in
the EEPROM Programming chapter, and downloads the EEPROM data from the transceiver to the
computer.
Store this data in a disk file so that it can be saved and retrieved later. Using the table below, program
the channel, CTCSS, and DCS alignment settings for your transceiver version. Upload this file to the
transceiver.
Note: Signal levels in dB referred to in this procedure are based on 0 dBm = 0.5 µV (closed circuit).
Set up the test equipment as shown for transmitter alignment.
Maintain the supply voltage at 13.8V DC for all steps.
50Ω
Dummy Load
Inline
Wattmeter
Deviation
Meter
Frequency
Counter
RF Sampling
Coupler
Transceiver
RF Signal
Generator
Power
Supply
VPL‑1
IBM PC
