4-22
D
About BPSK and QPSK modes
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.
q
During PSK mode selection, push [DECODE]
F-3
to display the PSK decode screen.
w
Push [<MENU1>]
F-1
to select PSK decode sec-
ond menu.
e
Push [B/QPSK]
F-2
to toggle between BPSK and
QPSK mode alternately.
<
MENU1
>
F-1
DECODE
F-3
B/QPSK
F-2
4
RECEIVE AND TRANSMIT
• PSK decode screen— BPSK mode
• PSK decode screen— QPSK mode
• Preamp
(p. 5-10)
➥
Push [P.AMP]
(MF3)
several times to set the
preamp OFF, preamp 1 ON or preamp 2 ON.
• Hold down [P.AMP] (MF3)
for 1 second to turn the
preamp function OFF.
• “P.AMP1” or “P.AMP2” appears when the preamp 1 or
preamp 2 is ON.
• Attenuator
(p. 5-10)
➥
Push [ATT]
(MF4)
several times to set the attenu-
ator in 6 dB steps.
• Hold down [ATT]
(MF4)
for 1 second to turn the
attenuator function OFF.
• “ATT” and attenuation level appear when the attenu
-
ator is ON.
• Noise blanker
(p. 5-17)
➥
Push
NB
to turn the noise blanker ON or OFF,
and then rotate [NB] control to adjust the thresh-
old level.
• Noise blanker indicator (above
NB
switch) lights
when the noise blanker is ON.
• Hold down
NB
for 1 second to enter noise blanker
set mode.
• Noise reduction
(p. 5-18)
➥
Push
NR
to turn the noise reduction ON or
OFF.
•
Rotate [NR] control to adjust the noise reduction level.
• Noise reduction indicator (above
NR
switch) lights
when the noise reduction is ON.
• Twin PBT (passband tuning)
(p. 5-13)
➥
Rotate [TWIN PBT] controls (inner/outer).
• PBT indicator (above
PBT-CLR
switch) lights when
PBT is in use.
• Hold down
PBT-CLR
for 1 second to clear the set-
tings.
• AGC (auto gain control)
(p. 5-12)
➥
Push [AGC] switch several times to select
AGC FAST, AGC MID or AGC SLOW.
➥
Push
AGC VR
to turn the AGC time constant
manual setting ON or OFF.
• Rotate [AGC] control to adjust the time constant.
• Manual notch filter
(p. 5-19)
➥
Push
NOTCH
to turn the manual notch function
ON or OFF.
• Rotate [NOTCH] control to set the attenuating fre
-
quency.
• Notch indicator (above
NOTCH
switch) lights when
the manual notch is ON.
• Fine tuning
(p. 3-7)
➥
During PSK, make sure that the kHz tuning step
function is OFF (no “
Z
” indication), hold down
[TS] for 1 second.
• PSK may not be decoded correctly using the 10 Hz
step tuning.
•
1
⁄
4
function
(p. 3-6)
➥
Push [1/4] to turn the
1
⁄
4
function ON or OFF.
D
Convenient functions for receive
l
About the 5 MHz frequency band operation (USA version only)
See page 4-3 for details.
