Philips D 2999 Manual page 6

SINGLE-SIDE BAND MODULATION (SSB)
In many amateur transmitters including transmitters
which are used for communication purposes and
weather forecasts, etc. so-called single side band
modulation Is used (either 'lower side band' LSB, or
'upper side band' USB).
These single side band or SSB transmitters can be
HEARD with a normal receiver but not be UN¬
DERSTOOD.
For an understandable reception of an SSB trans¬
mitter an auxiliary oscillator (BFO or 'beat frequen¬
cy oscillator') is required.
For more technical details see the booklet 'World
receiver'.
Tuning to SSB transmitters
• Set the 'AM GAIN' switch @ to 'MAN'.
• Turn 'AM GAIN' control © to 'MAX'.
• Increase the volume with VOLUME' control
• Accurately tune to the frequency or to the
maximum volume of the SSB transmitter (with BFO
switch @ still in the 'OFF' position).
• Set 'BFO' control @ to the mid position.
• Switch on the auxiliary oscillator with BFO switch
• Turn the VOLUME control @ to 'MAX'.
• Decrease the AM gain with AM GAIN' control @
until the meter @ does not fluctuate.
• Vary the BF0 frequency with BF0 control © until
the transmitter is received understandably.
• Check if the intelligibility increases by setting the
bandwidth switch @ to NARROW'.
• When very close to a transmitter, it may be
necessary to depress distant/local selector switch
© in order to reduce the sensitivity of the receiver.
Distant/local selector switch ©
By depressing distant/local selector switch © you
can reduce the sensitivity of the receiver. This
switch will usually be used when very close to a
transmitter. In the 'local' mode you will receive only
the local and/or very strong transmitters.
CLOCK
12 Hour or 24 Hour mode operation
A choice of 12 and 24-hour modes is available.
BEFORE inserting the memory batteries select a
mode with switch ©. Operating in the 12-hour
mode is confirmed by the AM/PM sign on the
display ©.
Actual Time setting
• Depress the 'TIME' button @.
• Depress the SET' button ©. The indicator TIME'
in the display © will start to blink. Moreover the
display will show '00.00' of which the most left one
will also blink.
• Depress FOUR buttons in the main keyboard ©;
the first button for the tens of hours, the second one
for the units of hours, the third one for the tens of
minutes and the fourth one for the units of minutes.
After each key-in the next zero will start blinking.
Note: When setting the time, a leading zero may
NOT be omitted: when e.g. setting to 8.15 hours,
you must key in 0 - 8-1 -5 followed by'EXECUTE'.
• In the 12-hours mode: set with the AM/PM
selector © to the required part of the day-time.
• Depress the 'execute' button on keyboard 0).
The blinking of the Tl ME' indicator in the display @
will stop.
Alarm Time Setting
Setting of the alarm can be done in the same way
as described for setting the actual time however the
first button in the operational sequence is now the
'ALARM' button
Then press 'SET' button (§). After pressing this
button the ALARM' indicator in the display © will
start blinking.
Switching the alarm on and off
• Press ALM ON/OFF' button ©.
• In the display @ a (((O))) sign will be visible
indicating that the alarm is switched on.
Switching Off the alarm tone
When the alarm tone sounds it can be switched off
by depressing 'ALM ON/OFF' button @. The sign
(((O))) in display© will disappear. If the alarm tone
is not switched off manually it is done automatically
after 59 minutes.
Note: As the alarm feature operates from the radio
batteries, accumulator or mains, continuity of
power supply must be maintained for it to function.
Carrying handle (See Fig. 1)
The carrying handle © is detachable. Proceed as
follows:
Unscrew both fixing screws © using a coin or
similar. When both screws are loosened the handle
can be removed. When replacing the carrying
handle position it such that it is in a position with
respect to the marking dot as shown and fix both
screws again.
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