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Idiomas disponibles
Idiomas disponibles
To Receive the SSB (Single Side Band)
Press SSB repeatedly while the radio is on.
Every press changes the display as follows.
(normal) —» USB —+ LSB/CW
What is SSB?
SSB is very popular among ham and business radio users and will be found on all of the
amateur bands because of its signal intelligibility.
In general, SSB transmissions employ USB modulation, and for amateur bands lower than
10 MHz, LSB is often used.
What is CW (Continuous Wave)?
CW is also popular among ham and business radio. In CW transmission, the amplitude of
a carrier is not modulated while that of other system is modulated. CW conveys informa-
tion by interrupting a carrier using Morse code. It can be heard as a beat sound only with
the unit equipped with the BFO circuits. To understand the information transmitted by
CW, you need to learn the Morse code.
To Receive the SYNC (Synchronous Detection)
Press SYNC repeatedly while the radio is on.
Every press changes the display as follows.
(normal) —> SYNC U —+ SYNC L
Let
When the synchronous detection is locked, "LOCK" indication appears in the display.
What is synchronous detection?
There are two big problems in AM reception: distortion due to fading and interference
from adjacent stations. The synchronous detection is effective in solving these problems.
Distortion due to fading is caused by over-modulation, which occurs when a carrier
component of the received signal is attenuated on the way. In this receiver, a pure carrier
frequency with no level variation, perfectly synchronized with the original carrier, is
generated in the synchronous detector circuit and is mixed with the received signal to
compensate the attenuated carrier component. In this way, distortion is remarkably
reduced.
On the other hand, AM (SW, MW, and LW) broadcasting generally uses double-sideband
transmission, in which modulated signals are transmitted using both the upper and lower
sidebands (USB and LSB). In most cases, one of the sidebands is affected by interference
from adjacent stations (beats). In the synchronous detector circuit, one of USB and LSB can
be received. This allows clear reception without interference from adjacent stations.
Amplitude
Carrier
LSB | USB
Interference from
adjacent station.
——
Only this side is
Remeney
received.
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