Yaesu FT-857 HF, Техническое дополнение

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21
Alignment
In case the transmission power is not within the speci-
fied tolerance, adjust this parameter for 20 W (±2 W)
of transmission power.
15.Select menu item “
42: VHF-MIN
.” Key the transmit-
ter, and confirm that the output power is 5 W (+0/–1
W). In case the power is not within the specified toler-
ance, adjust this parameter for 5 W (+0/–1 W) of trans-
mission power.
16.Tune the transceiver to the 430 MHz band in the CW
mode.
17.Select menu item “
43: UHF-MAX
.” Key the transmit-
ter, and adjust this parameter for 20 W (±1 W) of trans-
mission power.
18.Select menu item “
44: UHF-MID
.” Key the transmit-
ter, and confirm that the output power is 20 W (±0.3
W). In case the transmission power is not within the
specified tolerance, adjust this parameter for 20 W
(±0.3 W) of transmission power.
TX Gain Adjustment
1. Set the transceiver to the USB mode.
2. Inject a 1 kHz tone at 1 mV level to the MIC jack.
3. Tune the transceiver to the 1.8 MHz band.
4. Select menu item “
45: HF1TXG
.” Key the transmitter,
and adjust this parameter for 70 W (±10 W) of trans-
mission power.
5. The other TX gain adjustment menus, “
46: HF2TXG
,”
“
47: HF3TXG
,” and “
48: 50MTXG
,” should be ad-
justed in the same manner as detailed above on the 7
MHz, 21 MHz, and 50 MHz bands, respectively.
6. Tune the transceiver to the 144 MHz band.
7. Select menu item “
49: VHFTXG
.” Key the transmitter
and adjust this parameter for 35 W (±5 W) of trans-
mission power.
8. Tune the transceiver to the 430 MHz band.
9. Select menu item “
50: UHFTXG
.” Key the transmitter
and adjust this parameter for 10 W (±2 W) of trans-
mission power.
ALC (Automatic Level Control) Meter Adjustment
1. Tune the transceiver to the 21 MHz band in the USB
mode.
2. Select menu item “
51: ALC-1
.” Key the transceiver
without microphone input and press the [
A
] key. Now,
a value which the microprocessor computes will be
displayed on the LCD.
3. Rotate the main DIAL knob to adjust this parameter to
a reading four digits lower than the parameter value
displayed in the previous step.
4. After setting the parameter, confirm that all the dots of
the ALC meter have gone out.
5. Select menu item “
52: ALC-M
.” 1 kHz tone at 4 mV
level to the MIC jack.
6. Press the [
A
] key and confirm that the ALC meter
shows an “S-8” S-meter reading on the LCD.
AFP (Automatic Final Protection) Adjustment
1. Tune the transceiver to the 1.8 MHz band in the CW
mode, and connect a 150-Ohm dummy load to the an-
tenna jack.
2. Select menu item “
53: HF1-RV
.” Key the transmitter,
and adjust this parameter for an “S-8” S-meter reading
on the LCD.
3. The other AFP adjustment menus, “
54: HF2-RV
,” “
55:
HF3-RV
,” and “
56: 50M-RV
,” should be adjusted in
the same manner as shown above on the 7 MHz, 21
MHz, and 50 MHz bands, respectively.
4. Tune the transceiver to the 144 MHz band.
5. Select menu item “
57: VHF-RV
.” Key the transmitter,
and adjust this parameter for an “S-6” S-meter reading
on the LCD.
6. Tune the transceiver to the 430 MHz band.
7. Select menu item “
58: UHF-RV
.” Key the transmitter,
and adjust this parameter for an “S-3” S-meter reading
on the LCD.
Carrier Level Adjustment
1. Tune the transceiver to the 21 MHz band in the CW
mode.
2. Connect a 50-Ohm dummy load to the HF/50MHz
antenna jack.
8. Select menu item “
59: CW-CAR
.” Key the transmit-
ter, and adjust this parameter for an “S-9” S-meter read-
ing on the LCD.
3. Connect the oscilloscope to the HF/50MHz antenna
jack via an appropriate attenuator.
4. Set the transceiver to the AM mode.
5. Inject a 1 kHz tone at 1 mV level to the
MIC
jack.
6. Select menu item “
60: AM-CAR
.” Key the transmitter,
and adjust this parameter for 33% AM modulation on
the oscilloscope.