4 RECEIVE AND TRANSMIT

DConvenient functions for receive

• Preamp (p. 5-9)

 

 

 

• Twin PBT (passband tuning) (p. 5-12)

➥ Push [P.AMP] (MF3) several times to set the pre-

➥ Rotate [TWIN PBT] controls (inner/outer).

amp OFF, preamp 1 ON or preamp 2 ON.

• PBT indicator (above

 

PBT-CLR

switch) lights when

• “P.AMP1” or “P.AMP2” appears when the preamp 1 or

PBT is in use.

 

 

 

 

 

 

preamp 2 is ON.

 

 

 

• Push and hold

PBT-CLR

for 1 sec. to clear the set-

• Attenuator (p. 5-9)

 

 

 

tings.

 

 

 

 

 

 

 

 

 

 

 

• AGC (auto gain control) (p. 5-11)

➥ Push [ATT] (MF4) several times to set the attenu-

ator in 6 dB steps.

 

 

 

➥ Push

 

[AGC] switch

several

times to select

• Push and hold [ATT] (MF4) for 1 sec. to turn the atten-

AGC FAST, AGC MID or AGC SLOW.

uator function OFF.

 

 

 

➥ Push

 

AGC VR

 

to turn the AGC time constant

• “ATT” and attenuation level appear when the attenu-

manual setting ON and OFF.

 

ator is ON.

 

 

 

 

 

 

 

• Rotate [AGC] control to adjust the time constant.

• Noise blanker (p. 5-16)

 

 

 

• Manual notch filter (p. 5-18)

 

➥ Push

NB

to turn the noise blanker ON and

➥ Push

 

 

to turn the manual notch function

 

NOTCH

OFF, and then rotate [NB] control to adjust the

 

 

 

 

 

 

 

 

 

ON and OFF.

 

 

 

 

 

 

threshold level.

 

 

 

• Rotate [NOTCH] control to set the attenuating fre-

• Noise blanker indicator (above

 

NB

 

switch) lights

quency.

 

 

 

 

 

 

when the noise blanker is ON.

 

 

 

• Notch indicator (above

 

 

switch) lights when

 

 

 

NOTCH

• Push and hold

 

for 1 sec. to enter noise blanker

the manual notch is ON.

 

NB

 

set mode.

 

 

 

 

 

 

 

• Fine tuning (p. 3-7)

 

 

 

• Noise reduction (p. 5-17)

 

 

 

 

 

 

 

 

 

➥ During PSK, make sure that the kHz tuning step

➥ Push

NR

to turn the noise reduction ON and

 

 

 

 

Z

 

 

 

 

 

 

 

 

 

 

 

 

function is OFF (no “ ” indication), push and hold

OFF.

 

 

 

 

 

 

 

 

[TS] for 1 sec.

 

 

 

 

 

 

• Rotate [NR] control to adjust the noise reduction

• PSK may not be decoded correctly using the 10 Hz

level.

 

 

 

 

 

 

 

 

step tuning.

 

 

 

 

 

 

• Noise reduction indicator (above

NR

switch) lights

• 1⁄4 function (p. 3-6)

 

 

 

when the noise reduction is ON.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

➥ Push [1/4] to turn the 1⁄4 function ON and OFF.

DAbout BPSK and QPSK modes

<MENU1> B/QPSK DECODE

F-1

F-2

F-3

• PSK decode screen— BPSK mode

BPSK and QPSK modes are available for PSK31.

•BPSK (Binary Phase Shift Keying) mode is the most commonly used mode.

•QPSK (Quadrature Phase Shift Keying) mode has error correction capability to provide better decoding than BPSK mode in marginal condition. However, more accurate tuning is required with QPSK mode, due to the tight phase margin of QPSK.

qDuring PSK mode selection, push [F-3•DECODE] to display the PSK decode screen.

wPush [F-1•<MENU1>] to select PSK decode second menu.

ePush [F-2•B/QPSK] to toggle between BPSK and QPSK mode alternately.

• PSK decode screen— QPSK mode

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