Yaesu FT-2400H Technical Supplement page 18

the need for realignment determined to be abso­
lutely 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 im­
proper 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 ad­
justments be performed afterwards. Do not at­
tempt to perform only a single step unless it is
clearly isolated electrically from all other steps.
Rather, have all test equipment ready before begin­
ning, and follow all of the steps in a section in the
order presented.
Required Test Equipment
D RF Signal Generator with calibrated output
level at 200 MHz
D Deviation Meter (linear detector)
D Oscilloscope
D AF Millivoltmeter
0 SINAD Meter
D Inline Wattmeter with 5% accuracy at 200 MHz
D Regulated DC Power Supply adjustable from 10
to 17V, 15A
0 50-Q Dummy Load: 100W at 200 MHz
D Frequency Counter: ± 0.2 ppm accuracy at 200
MHz
D AF Signal Generator
D DC V oltmeter: high impedance
D Spectrum Analyzer
D VHF Sampling Coupler
Alignment Preparation
A 50-Q dummy load and inline wattmeter must
be connected to the main antenna jack in all proce­
dures that call for transmission, except where
specified otherwise. Correct alignment is not possi­
an
ble with 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.
4-2
ALIGNMENT
&
Precautions
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 - 86 °F).
is
When the transceiver
hot or cold air it should be allowed some time for
thermal equalization with the environment before
alignment.
Alignments must only 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 align­
ment procedure are based on 0 dBµ= 0.5 dBµV.
&
PLL Transmitter
Set up the test equipment as shown here for
transmitter alignment. Maintain the supply vol­
tage at 13.6V for all steps.
PLL & Transmitter Ali gn ment Setu p
50-ohm
Dummy Load
Freq. Counter
Spectrum
Analizer
Oscilloscope
Deviation
Meter
PLL V CV (V aractor Control Voltage)
D Connect the positive lead of the DC voltmeter to
the test point near Cl 141 on the Main Unit, as
indicated below, and the negative lead to chassis
ground.
test point
brought into the shop from
Regulated
AF Generator
AF Millivoltmeter