VXR-7000U
K66VXR-7000U_Alignment.doc
r IBM PC / compatible Computer with MS-DOS or later operating system
r Yaesu VPL-1 Connection Cable & CE-27 Channel/Alignment Diskette
Alignment Preparation & Precautions
A 50 Ω RF Dummy Load and in-line wattmeter must be connected to the TX 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, in connected)
before proceeding.
Correct alignment requires that the ambient temperature be the same as that of the repeater and test
equipment, and that this temperature be held constant between 20º and 30 °C (68º ~ 86 °F). When the
repeater is brought into the shop from hot or cold air, it should be allowed time to come to room
temperature 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 the alignment procedure are based on 0dBµ = 0.5µV.
Set up the test equipment as shown below, and apply AC power to the repeater.
The repeater must be programmed for use in the intended system before alignment is attempted. The
frequency and other parameters are loaded from the file during the alignment process.
In order to facilitate alignment over the complete switching range of the equipment it is recommended
that the channel data first be uploaded and then stored to disk. Channels at the upper, lower and middle
band edges should then be downloaded. The original data can be replaced at the end of the alignment
process.
CHANNEL FREQUENCY
Low band edge450.000 MHz
Center 465.000 MHz
High band edge 480.000 MHz
Transmitter
Press the BASE/REPEATER switch on the front panel of the repeater so as to set it to the “BASE”
mode if the REPEATER LED is on. You should see the REPEATER LED turn off, indicating that
the repeater is now in the “BASE” mode.
PLL VCV (Varactor Control Voltage) Check
r Connect the DC voltmeter between the VCV check point (on the TX Unit) and chassis ground.
r Select the High band edge channel, and then key the repeater. Confirm that the DC voltmeter
reading is 4.2•}0.3 VDC.
PLL Reference Frequency Adjustment
r Select the Center channel, and then key the repeater.
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