Vertex Standard FT-2000 ユーザーズマニュアル
Page 70
FT-2000 O
PERATING
M
ANUAL
A
DJUSTING
THE
SSB T
RANSMITTED
B
ANDWIDTH (SSB M
ODE
)
For transmission on SSB, a default bandwidth of 2.4 kHz is provided. This bandwidth provides reasonable fidelity along
with good talk power, and is typical of the bandwidth used for decades during SSB transmission. However, the bandwidth
may be varied by the operator, so as to provide different levels of fidelity or talk power, according to your preferences.
with good talk power, and is typical of the bandwidth used for decades during SSB transmission. However, the bandwidth
may be varied by the operator, so as to provide different levels of fidelity or talk power, according to your preferences.
E
NHANCING
T
RANSMIT
S
IGNAL
Q
UALITY
Here’s how to adjust the transmitted bandwidth on SSB:
1. Press the [MENU] button to engage the Menu.
2. Rotate the Main Tuning Dial knob so as to select Menu
1. Press the [MENU] button to engage the Menu.
2. Rotate the Main Tuning Dial knob so as to select Menu
item “083 A3J TX BPF.”
3. Rotate the [SUB VFO-B] knob to select the desired
bandwidth. The available selections are 3000/
50-3000/100-2900/200-2800/300-2700/400-
2600
50-3000/100-2900/200-2800/300-2700/400-
2600
, and the default is 300-2700 Hz. A wider band-
width will provide greater fidelity, while a narrow band-
width will compress the available transmitter power
into less spectrum, resulting in more “talk power” for
DX pile-ups.
width will compress the available transmitter power
into less spectrum, resulting in more “talk power” for
DX pile-ups.
4. Press and hold in the [MENU] button for two seconds
to save the new setting and exit to normal operation.
A
DVICE
:
The Transmit Monitor is very helpful way of verifying
the effects on fidelity of changing the bandwidth. Press-
ing the [MONI] button then adjusting the [MONI] knob
for a comfortable listening level while you are trans-
mitting, you will be able to hear the difference in sound
quality as you make changes.
ing the [MONI] button then adjusting the [MONI] knob
for a comfortable listening level while you are trans-
mitting, you will be able to hear the difference in sound
quality as you make changes.
When the optional DMU-2000 Data Management Unit
is connected, you may verify the effect of your adjust-
ments of the transmitted bandwidth by observing the
Audio Scope on the “Oscilloscope” page.
ments of the transmitted bandwidth by observing the
Audio Scope on the “Oscilloscope” page.
Main Tuning Dial Knob
[SUB VFO-B] Knob
[MENU] Button
Q
UICK
P
OINTS
:
The higher fidelity associated with wide bandwidth will
be particularly enjoyable on the low bands, during lo-
cal rag-chew QSOs.
cal rag-chew QSOs.
The “3000” setting is a special hi-fidelity setting,
whereby the transmitted bandwidth is in excess of 3
kHz. This selection, in conjunction with judicious ad-
justment of the Parametric Microphone Equalizer (see
next chapter) can provide truly outstanding fidelity and
very natural-sounding audio.
kHz. This selection, in conjunction with judicious ad-
justment of the Parametric Microphone Equalizer (see
next chapter) can provide truly outstanding fidelity and
very natural-sounding audio.
When using the wider bandwidth selections (especially
“3000”), the apparent power output from the transmit-
ter may seem lower. This is because the available power
from the transmitter is being distributed over a wider
bandwidth, and the power detection circuitry does not
compensate for the effect of the bandwidth selection
(it is calibrated in the default 2.4 kHz bandwidth).
ter may seem lower. This is because the available power
from the transmitter is being distributed over a wider
bandwidth, and the power detection circuitry does not
compensate for the effect of the bandwidth selection
(it is calibrated in the default 2.4 kHz bandwidth).