ENHANCING TRANSMIT SIGNAL QUALITY

ADJUSTING THE SSB TRANSMITTED BANDWIDTH (SSB MODE)

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.

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 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, and the default is 300-2700Hz.Awider 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.

4.Press and hold in the [MENU] button for two seconds to save the new setting and exit to normal operation.

ADVICE:

￿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.

￿When the optional DMU-2000Data 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.

[MENU] Button

Main Tuning Dial Knob [SUB VFO-B] Knob

QUICK POINTS:

￿The higher fidelity associated with wide bandwidth will be particularly enjoyable on the low bands, during lo- 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.

￿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).

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FT-2000 OPERATING MANUAL