Yaesu FT-277R, Manual

Page: 11 / 34

11
FT-277R Technical Supplement
RF Front-end Tuning
1. Connect the DC voltmeter to TP1031 on the MAIN unit,
then inject a 440.000 MHz signal at a level of +10 dBµ
(with 1 kHz modulation @±3.5 kHz deviation) from
the RF signal generator.
2. Rotate the DIAL knob to select the display to “B0106.”
3. Press the [ F/W
] key, then press the [
MR/MW
(
SKIP
)]
key to set the alignment parameter to “
A1 TUN.xxx
.”
4. With in five second of appearing the “
A1 TUN.xxx
” on
the display, adjust the DIAL knob so that the DC volt-
meter reaches maximum deflection. The FT-277R RF
Front-end has a broad bandwidth. Therefore, prior to
adjustment you must adjust the
DIAL knob to set the
frequency to the middle of the band, in step 2, so you
can set peak in the DC voltmeter’s deflection in the
center of the RF passband.
TX Power Output
1. Rotate the DIAL knob to select the display to “B0206,”
then set the transmit power level to “LOW.”
2. Press the [ F/W
] key, then press the [
MR/MW
(
SKIP
)]
key to set the alignment parameter to “
A2 PWR.xxx
.”
3. With in five second of appearing the “
A2 PWR.xxx
”
on the display, press the PTT switch to activate the
transmitter, adjust the DIAL knob so that the watt-
meter reading is 0.5 Watts (±0.05 Watt).
4. Increase the Transmit power level to “MID.”
5. Press the [
F/W
] key to recall the alignment parameter
“
A2 PWR.xxx
.”
6. With in five second of appearing the “
A2 PWR.xxx
”
on the display, press the PTT switch to activate the
transmitter, adjust the DIAL knob so that the watt-
meter reading is 2.0 Watts (±0.1 Watt).
7. Increase the Transmit power level to “HIGH.”
8. Press the [
F/W
] key to recall the alignment parameter
“
A2 PWR.xxx
."
9. With in five second of appearing the “
A2 PWR.xxx
”
on the display, press the PTT switch to activate the
transmitter, adjust the DIAL knob so that the watt-
meter reading is 5.0 Watts (±0.1 Watt).
TX Deviation
1. Rotate the DIAL knob to select the display to “B0206,”
then set the transmit power level to “LOW.”
2. Press the [ F/W
] key, then press the [
MR/MW
(
SKIP
)]
key to set the alignment parameter to “
A3 DEV.xxx
.”
3. With in five second of appearing the “
A3 DEV.xxx
” on
the display, press the PTT switch to activate the trans-
mitter, adjust the DIAL knob so that the deviation
meter reading is 4.5 kHz (-0.3 kHz) (EXP version: 4.5
kHz ± 0.2 kHz).
DCS TX Deviation
1. Rotate the DIAL knob to select the display to “B0206,”
then activate the DCS, and set the transmit power level
to “LOW.”
2. Press the [ F/W
] key, then press the [
MR/MW
(
SKIP
)]
key to set the alignment parameter to “
A4 DCS.xxx
.”
3. With in five second of appearing the “
A4 DCS.xxx
” on
the display, press the PTT switch to activate the trans-
mitter (with no microphone input), adjust the DIAL
knob so that the deviation meter reading is 0.7 kHz
(±0.05 kHz).
Alignment
TP1031