Vertex Standard VX-4000V Service Manual page 22

Alignment
Before beginning, connect the transceiver and PC
using the CT-71 programming cable as described in
the EEPROM Programming chapter, and download
the EEPROM data from the transceiver to the com-
puter.
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 proce-
dure are based on 0 dBµ = 0.5 µV (closed cir-
cuit).
Caution:Do not connect this line to ground, and be
certain that the speaker has adequate ca-
pability to handle the audio output from
the radio.
Because of the bridge audio amplifier cir-
cuit used in the radio, it is necessary to con-
struct and use a simple audio load test
adapter as shown in the schematic diagram
above, when conducting receiver align-
ment steps.
Alignment Channel Frequencies
VHF TYPE A
Frequency CTCSS
Channel
(simplex) Encode
CH1 134.01 MHz None
CH2 147.01 MHz None
CH3 159.99 MHz None
CH4 134.01 MHz None
CH5 147.01 MHz None
CH6 159.99 MHz None
CH7 147.01 MHz 151.4 Hz
CH8 147.01 MHz None
CH9 147.01 MHz 151.4 Hz
CH10 147.01 MHz None
VHF TYPE C
Frequency CTCSS
Channel
(simplex) Encode
CH1 148.01 MHz None
CH2 161.01 MHz None
CH3 173.99 MHz None
CH4 148.01 MHz None
CH5 161.01 MHz None
CH6 173.99 MHz None
CH7 161.01 MHz 151.4 Hz
CH8 161.01 MHz None
CH9 161.01 MHz 151.4Hz
CH10 161.01 MHz None
5-2
DCS
Narrow/wide
Encode
None Wide
None Wide
None Wide
None Narrow
None Narrow
None Narrow
None Wide
023 Wide
None Narrow
023 Narrow
DCS
Narrow/wide
Encode
None Wide
None Wide
None Wide
None Narrow
None Narrow
None Narrow
None Wide
023 Wide
None Narrow
023 Narrow
PLL & Transmitter
Set up the test equipment as shown for transmit-
ter alignment.
Maintain the supply voltage at 13.8 V DC for all
steps.
50-Ohm
Dummy Load
Inline Wattmeter
RF Sampling
Deviation Meter
Coupler
CT-71 connection
Cable
Frequency
Counter
PLL VCV
r Connect the positive lead of the DC voltmeter to
the test point TP1007 (VCV) on the Main Unit,
as indicated in the figure, and the negative lead
to chassis ground.
r Set the transceiver to the high band edge fre-
quency channel, then adjust L1021 on the Unit
for 4.2 V (VHF-A), 4.3 V (VHF-C) on the voltme-
ter.
r Key the transmitter, and adjust L1022 on the Unit
for 4.2 V (VHF-A), 4.3 V (VHF-C) on the voltme-
ter.
r Next select to the low edge frequency channel
and confirm 0.8 V on the voltmeter.
r Key the transmitter, and confirm 1.0 V on the
voltmeter.
PLL Reference Frequency
With the wattmeter, dummy load and frequency
counter connected to the antenna jack, and select
band center frequency channel, key the transmitter
(Low power level) and adjust TC1001 on the Main
Unit, if necessary, so the counter frequency is with-
in 100 Hz of the channel center frequency for the
transceiver version.
Transmitter Output Power
The following transmitter parameters can be ad-
justed from the computer by utilizing the Alignment
Software. Refer to the onboard help of the Align-
ment Software Manual for details.
HIGH Power 50 ± 1 W
LOW Power 25 ± 0.5 W
RF Signal
Generator
Transceiver
Power Supply
PC
13.8V DC
COM port
VX-4000 VHF Service Manual