Filter
Top Products
Note:
The Zero-in Point can be easily located because the Sound
loses its clarity suddenly when the frequency
Passes
away
from the Zero-in Point.
If
a clear Sound cannot be heard by
following the above procedure, it may be an indication that
the
Signal
is LSB. Set the MODE switch to LSB Position. In
this case, the setting of the VFO knob should be made in
reverse
Order.
Transmission
1. Set the MODE switch to USB and the meter switch to
ALC/CEN.
Other controls remain the same as outlined in
section on “FM Mode”.
2. Adjust the microphone gain. This adjustment should be
made with the standby switch set to SEND or the
microphone PTT switch depressed.
Next, speak into the microphone and adjust the SSB
Mic gain control on the front Panel, making sure that the
ALC meter does not deflect beyond the ALC zone.
After completion of the above adjustment, set the meter
switch to RF.
Note:
Periodically check the ALC meter deflection. lf, due to
heat, etc.,
there iS a Change in deflection, reset the
meter to within the ALC Zone.
Discrimination between SSB and FM
1. Use of S meter
If
the S meter is steady (meter pointer almost Stops), the
incoming
Signal
is FM; otherwise, it is SSB.
2. Use of MODE switch
If
a clear
Signal
is heard at the FM Position of the MODE
switch, the
Signal
is FM. The Sound in SSB mode is not
heard at this Position.
Use of RIT Switch
For detailed information, refer to section on “FM
Mode”. In SSB mode, if the receive frequency has drifted,
set the RIT switch to ON and adjust the RIT knob, as in the
case
of FM mode.
When the RIT switch is ON, the receive frequency is
off-
set from the transmit frequency, so it is necessary to turn
the switch off when tuning to another frequency.
Use of NB (noise blanker) Switch
The NB switch is used to suppress pulse noise such as
ignition noise generated by car engine.
Use of RF GAIN Control
For detailed information, refer to section on “FM
Mode”. Normally, this control should be left in full
clockwise position. When a very strong incoming
Signal
is
present, turn it counterclockwise. The noise
level
below
the receive
Signal
level
is attenuated for clear reception.
If the RF GAIN is reduced excessively in SSB or CW
mode, the S meter deflection will increase irrespective of
incoming
Signal
strength. This is due to the circuit
characteristics and is not an indication of trouble.
The secret of reading accurate
Signal
strength is to turn
the RF GAIN control counterclockwise so that it is a little
lower than the
Signal
level
read on the S meter at the full
clockwise Position, as shown in Fig. 13.
Maximum S meter reading
of an incoming signal.
I
I
Meter deflection
hl
clockwise
Signals
weaker
with RF GAIN
Position
counter-
clockwise.
Fig. 13 RF GAIN Control Setting
5-4
IF
SHIFT Control
The IF SHIFT control is used to shift the passband of the
IF filter without changing receive frequency. By turning this
control in either direction, the
IF
passband is shifted as
shown in Fig. 14.
The IF SHIFT is effective in eliminating interference
when the receive
Signal
is superimposed on nearby
Signals
during Operation in both SSB and CW modes.
Turning the control in
“+”
direction will eliminate in-
terference from low frequency
Signal.
In this way, the low
frequency component in the
Signal
is
cut
off.
Turning the control in ”
-
”
direction will eliminate in-
terference from high frequency
Signal.
The high frequency
component is
cut
off accordingly.
Turned in
“-
”
Turned in ” + ”
direction
IF
filter passband direction
c
characteristic
*
I2erfering Signal
‘,‘+d
I”WI
Teupo;
,-;;,;;;
“n
;,+;;,v:
nate interference
nate tnterference
from
Signal
B
from Signal A
Fig. 14
IF
SHIFT Control
13