Vertex Standard VX-1700 Series, Service Manual

Page: 12 / 116

12
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 ap-
ply 13.8V DC power to the transceiver.
The VX-1700 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
operating range of the equipment, it is recommend-
ed that the channel data first be uploaded and then
stored to disk. Alignment Channel data should then
be downloaded. The original data can be replaced at
the end of the alignment process.
Reference & Local Alignment
PLL R
EFERENCE
F
REQUENCY
A
LIGNMENT
ˆ
Connect the Frequency Counter to pin 4 of Q1062
(Lot. 1~6) or TP1073 (Lot. 7~) on the MAIN Unit.
ˆ
Adjust X1003 on the MAIN Unit (Lot. 1~6) or
Trimmer on the REF Unit (Lot. 7~) for 22.625 MHz
±10 Hz on the frequency Counter.
2
ND
L
OCAL
O
UTPUT
L
EVEL
ˆ
Connect the RF millivoltmeter to TP1043 on the
MAIN Unit.
ˆ
Adjust T1013 on the MAIN Unit for 160 mVrms
(±50 mVrms) on the RF millivoltmeter.
PLL Alignment
VCO VCV A
LIGNMENT
Connect the DC voltmeter to TP1048 on the MAIN
Unit, and referring to the Table below, switch the
transceiver to each channel listed. Then adjust the
listed component for the required voltage or confirm
that the correct voltage is present.
PLL O
UTPUT
L
EVEL
ˆ
Connect the RF millivoltmeter to TP1039 on the
MAIN Unit, then tune the radio to 7.500 MHz.
ˆ
Confirm that the output level is more than 10
dBm.
Tune to
13.499 MHz
0.100 MHz
29.999 MHz
13.5000 MHz
Adjust or Confirm
Adjust T1066
Confirm
Adjust T1067
Confirm
For
5.2 V ± 0.1 V
More than 0.6 V
5.3 V ± 0.1 V
More than 0.5 V
Transceiver
Inline
Wattmeter
Power Supply
13.8 VDC
Frequency
Counter
RF
Signal Generator
50-ohm
Dummy Load
TUNER
COM Port
CE77 Programming Software
ANT
RF Sampling
Coupler
INPUT
CT-62
Programming Cable