4 RECEIVE AND TRANSMIT

DConvenient functions for receive

• Preamp (p. 5-9)

 

 

 

 

 

 

 

 

• Noise reduction (p. 5-17)

 

 

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

➥ Push

 

 

to turn the noise reduction ON and

 

NR

amp OFF, preamp 1 ON or preamp 2 ON.

OFF.

 

 

 

 

 

 

 

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

• Rotate [NR] control to adjust the noise reduction

preamp 2 is ON.

 

 

 

 

 

 

 

 

level.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

• Noise reduction indicator (above

 

switch) lights

• Attenuator (p. 5-9)

 

 

 

 

 

 

NR

 

 

 

 

 

 

when the noise reduction is ON.

 

 

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

• Manual notch filter (p. 5-18)

 

 

ator in 6 dB steps.

 

 

 

 

 

 

 

 

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

➥ Push

 

NOTCH

to turn the manual notch function

uator function OFF.

 

 

 

 

 

 

ON and OFF.

 

 

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

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

ator is ON.

 

 

 

 

 

 

 

 

quency.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

• Notch indicator (above

 

switch) lights when

• Noise blanker (p. 5-16)

 

 

NOTCH

 

 

the manual notch is ON.

 

 

➥ Push

NB

to turn the noise blanker ON and

• AGC (auto gain control) (p. 5-11)

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

threshold level.

 

 

 

 

 

 

 

 

➥ Push

[AGC] switch several times to select

• Noise blanker indicator (above

 

 

switch) lights

AGC FAST, AGC MID or AGC SLOW.

 

NB

when the noise blanker is ON.

 

 

➥ Push

AGC VR

to turn the AGC time constant

• Push and hold

 

 

 

for 1 sec. to enter noise blanker

manual setting ON and OFF.

 

 

 

NB

 

 

 

set mode.

 

 

 

 

 

 

 

 

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

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

• 1⁄4 function (p. 3-6)

 

 

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

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

• PBT indicator (above

 

PBT-CLR

switch) lights when

 

 

 

 

 

 

 

 

 

PBT is in use.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

• Push and hold

 

PBT-CLR

for 1 sec. to clear the set-

 

 

 

 

 

 

 

 

 

tings.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DAbout RTTY reverse mode

NormalReverse

 

170 Hz

 

2125 Hz

 

 

 

2125 Hz

170 Hz

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Space Mark BFO

BFO Space Mark

Received characters are occasionally garbled when the received signal has Mark and Space tones re- versed. This reversal can be caused by incorrect TNC connections, setting, commands, etc. To receive reversed RTTY signals correctly, select RTTY-R mode.

➥During RTTY mode, push and hold RTTY/PSK for 1 sec. to select RTTY and RTTY-R mode.

DTwin peak filter

APF/TPF

The twin peak filter changes audio frequency response by boosting the mark and space frequencies (2125 and 2295 Hz) for better reception of RTTY signals.

➥During RTTY mode, push APF/TPF to turn the twin peak filter ON and OFF.

•“ TPF ” appears in the LCD and the [APF/TPF] indicator above this switch lights green while the filter is in use.

NOTE: When the twin peak filter is in use, the re- ceived audio output may increase. This is a normal, not a malfunction.

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