Lab599 Discovery TX-500, Руководство пользователя

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MODE SELECTION
Each mode is described briefly below. Later sections cover each mode in detail. Tap
D
one or more times to select USB (LSB), CW (CWR), DIG, AM or FM mode. Long push
selects alternate modes, such as CW reverse (CWR). Also, long push returns normal mode.
•
SSB modes: Mode is a narrow-banded voice mode that conserves space in crowded
band segments. It’s the most popular mode overall. LSB (lower sideband) is usually used
on 160, 80, and 40 meters, while other bands use USB (upper sideband).
• CW mode requires very little bandwidth, providing a high signal-to-noise ratio that’s ideal
for low-power use. It’s also a popular mode for DXing and contests.
• CWR mode reversing the received sideband in CW mode. This may reduce the level
of interference (QRM).
•
AM mode
is characterized by its good fidelity. It is much less power-efficient than SSB.
• AM amateur operation is often found on 160, 80, 40, and 10 meters.
• FM mode is most often used for local communications, and can be found on 10m and up.
•
DIG mode
typically use a computer connected to the transceiver to send/receive text.
Although SSB modes can also be used for this purpose, the TX-500’s audio-based data
modes (
E
) optimize settings for data rather than voice.
VFOs A and B
The TX-500 provides two VFOs. Use of VFO B is optional. Each VFO has independent
frequency, mode, and filter settings:
•
VFO A normally controls both the receive and transmit frequency. Most contacts occur
between stations tuned to about the same frequency.
• VFO B can serve as a holding register for a second frequency of interest, then swapped
with VFO A as needed (see A<>B).
•
+ - Tuning rates:
Tapping K or L selects VFO tuning rate LSB, USB, DIG (10Hz, 100Hz,
1kHz, 2.5kHz, 5kHz), CW, CWR (1Hz, 10Hz, 100Hz, 1kHz, 2.5kHz), AM, FM (100Hz, 500Hz,
1kHz, 2.5kHz, 5kHz). SSB stations often align on 0.5 or 1.0kHz boundaries.
• A->B To copy VFO A’s frequency to VFO B: Tap
N>
A->B
. Tapping also copies VFO
A’s mode and filter settings to VFO B as well.
•
B->A
To copy VFO B’s frequency to VFO A: Tap
N>
B->A
. Tapping also copies VFO
B’s mode and filter settings to VFO A as well.
• A<>B VFO A and B swap: Tap
N>
A<>B
to exchange VFO frequencies, modes, and
all other settings.
RIT
Incremental Tuning, or receive incremental tuning, provides a means of adjusting the
receive frequency without affecting your transmit frequency. This control is sometimes
called a clarifier since it can be used to tune in SSB voice signals. But RIT can also be used
in all modes, in the event that a station calls you slightly off-frequency. RIT and XIT use the
tuning rate (1/10/100/200/300 Hz), taping
K or L .
XIT
XIT or transmit incremental tuning, adjusts the transmit frequency without affecting the receive
frequency. RIT and XIT use the tuning rate (1/10/100/200/300 Hz), taping
K or L .
• To use RIT or XIT: First, tap G RIT (RX mode) or tap G XIT (TX mode).
This turns on the "+0" on the display. Then adjust the offset using RIT/XIT knob.
• To zero the RIT/XIT offset tap
H
.
J
VFO lock/unlock
When the mode is activated, the inscription appears in the upper line of the display "LOCK",
frequency tuning is not possible. To deactivate the mode, press the button
J again.
TRANSMIT SETTINGS
• Voice Modes (SSB, AM, FM)
Choose a mode: Tap
D
to select
A
/
B
,
F
or
G
mode.
•
MON, Monitor
Push
N>
MON
in the bottom line for MON on. Hold PTT to set the voice
monitor level, rotate
M
AF GAIN knob. High MON settings may result in audio clipping or
distortion. Start with 3 to 5.
Do not use the hand speaker-mic at the same time as monitor
F
function
in voice modes:
A B F G
• Adjust mic gain level Push
METR
and select MIC, rotating
M
TUNE/MULTI.
While speaking into the mic, adjust
F> 09 > Gain > MIC
(mic gain).
While speaking, adjust mic gain for maximum 10 bars on a scale. Mic gain for the
TX-500 mic is typically 10-20.
• CMR Speech compression: To use speech compression, tap
N>
CMR
in the top line.
Basic Operations
CMR ECHO VOX D METR
Menu Up Menu Down SubMenu
TX Metr MIC
+
12
+
<< TONE MON >>
F
!
TX-500’s receive filter passband. In general, a narrow passband reduces interference
(QRM) and noise (QRN), while a wider passband improves fidelity. In voice modes, CW
and DIG modes long push
E
selects low-cut (LF) and high-cut (HF) frequency.
Pushing
E
select number of filter (1-4)RX, (1-2)TX. These functions remove low- or
high-pitched interfering signals. Reducing the width or shifting the passband may attenuate
an interfering signal above or below the desired one.
• PRE/ATT Preamp
L
and Attenuator
D
turns on the RF preamp. It should be used
only when signals are very weak. Preamp gain can be set on a per-band basis.
D
turns
on the 20-dB RF attenuator, which can protect the receiver from strong interfering signals.
• NR
Noise reduction removes random background noise (hiss or static). It has a
characteristic “hollow” sound. Higher settings may attenuate weak signals. Tap
N>
NR
turns on noise reduction, holding
N>
NR
and displays its setting, which can be adjusted
using the knob
M
TUNE/MULTI . Tap return to exit the setting display. Tap
N>
NR
again
to turn noise reduction off.
• NB Noise blanking
C
can eliminate repetitive noise such as that from power lines,
appliances, and vehicle ignitions systems. The NB setting is adjusted in the same way as
NR (see above).
• NF in SSB and AM modes,
B
turns on auto-notch, which locates and suppresses one
or more carriers automatically, Push
N>
NF
to enable or disable the Notch Filter.
• TONE (Transmission tone). The transceiver will transmit a single tone. Pressing “Tone”
N>
TONE
again puts the transceiver in RX mode. A long press of
TONE
displays the
selection mode
NORMAL
(1000 Hz) or
DUAL
(two tones of 1000 Hz and 2000 Hz).
The transmission power is approximately 50%.