Realistic DX-440 warranty DIBmJ

Models: DX-440

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SPECIAL SSB/CW RECEPTION TECHNIQUES

Many stations transmit unmodulated telegraph transmissions in the shortwave

band. To receive these special Morse code characters, the radio uses a special circuit, a beat-frequency oscill - ator, to modify the transmitted signal so that you can hear it. This particular type of telegraph transmission is called Con- tinuous wave (CW) transmission.

Many stations transmit voice signals with a suppressed carrier in the single side band.(SSB),part of the radio trans- mission spectrum that lies to the side of the primary frequency signal. Amat- eurs tend who transmit voice below 10 MHz use the lower side band (LSB).

Above 10 MHz, they use the upper side band (USB). Commercial utility stations generally use the USB. A carrier has to be added to make these signals audible.

4. Rotate the BFO PITCH control to the

 

 

midpoint.

BFO PITCH

RF GAIN

'"

 

 

00USB MIN

5. Rotate the RF GAIN control to the

 

RF GAIN

MAX position

BFO PITCH

 

 

 

 

 

BFO HTCH

RF GAIN

TO RECIEVE CW

 

00use M,.. ..~x

1.

Turn on the radio.

 

 

POWER

 

 

 

i'

 

 

 

 

 

 

MINI I I I I I I I [

I IMAX VOLUME

 

 

~

 

 

 

 

 

2.

Extend the antenna fUlly straight up.

 

 

 

3. Set the BFO switch to IN.

iFMi

MONO STEREO BFO LOCK

!DIBmJ. . .. ..

WIDE NARROW OUT"*'IN OUT iN

LAM-.J

6. Press the AM band button to select

 

 

 

the AM band.

FM AM LW MW SW

00000

 

 

i'

 

 

7. Tune in the CW station using the

 

 

 

tuning knob, or enter the frequency

LIIIIIIIIIIIR

BALANCE

 

using the direct access buttons.

~

 

 

LOIIIIIIIIIIIHI

TREBLE

 

 

~

 

 

 

 

i'

 

ODD456

 

CJ CJ CJ

 

7

8

9

 

CJ CJ CJ

 

O/SEC

EXECUTE

 

 

CJ (

 

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Realistic DX-440 warranty DIBmJ