Yaesu FT-2500M, Техническое дополнение

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Alignmen
Receiver
Set up the test equipment as shown below for
receiver alignment.
Receiver Alignment Setup
RF Signal
Generator
Interstage Transformers
Regulated
13.BV PSU
Speaker or
4
-ohm
lead. resistor
AF
Millivoltmeter
SINAD Meter
Distortion
Meter
0
Connect the DC voltmeter between J1 003 pin
7 and chassis ground.
0 Modulate the RF signal generator with ±3.5
kHz deviation of a 1-kHz tone.
0 Adjust T1001 - T1 004, & T1006 on the Main
Unit for maximum voltage on the meter, then
once again for optimum SINAD (at least -7
dBµ for 12 dB SINAD).
S-Meter Calibration
0 While tuned to 1 46.000 MHz, inject a +25 dBµ
RF signal modulated with ±3.5 kHz deviation
of a 1-kHz tone, and adjust VR2006 on the
CNTL Unit so that all S-meter segments are
just on.
Scanner Center Stop
0 Connect the DC voltmeter (3-V range) be­
tween TP2002 ( +) and TP2001 (-) on the CNTL
Unit.
0
With both the transceiver and signal generator
tune to 1 46.000 MHz, set the
SOL
control fully
counter-clockwise (the
"BUSY "
indicator
should be on). Inject 20 dBµ RF modulated
with ±3.5 kHz deviation of a 1-kHz tone, and
adjust VR2007 on the CNTL Unit for 0 V on the
voltmeter.
Squelch
0 Preset the SQL control to the 1 0 o'clock posi­
tion. At the center of the band, tune the
RF
signal generator to the same frequency, and set
the generator level to -12 dBµ .
0
Tum VR1 001 clockwise until the squelch just
closes, and then counter-clockwise very
slightly so that it just opens.
Receiver Alignment Points
T 1 00 1
T1 002
T1 003
T1 004
VR2007
T 1 006
TP2001 ( - )
J 1 003 Pin?
TP2002 ( + )
VR1 00 1
VR2006
2-8
FT-2500M Technical Supplement