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TV SOUND MODULATOR
PROGRAMMING
After having installed the unit, programming can
be started. Connect the PROGRAMMER to the 6-pin
socket on the front plate. After the short display of "no
co" (no connection), the operation mode of the unit is
displayed. Any other display or flashing indicates some
fault in functioning. In this case consult the PRO-
GRAMMER's manual that gives further useful informa-
tion on programming, too.
• With the PROGRAMMER, the programmable pa-
rameters, as menu items, can be stepped round. This
guide describes the setting of the parameters in the
sequence of their appearance in the menu. (The TV
SOUND MODULATOR has only one porgramma-
ble parameter.)
• The desired numeric values can be set by stepping
fast or slowly, or they can be set directly from the
numeric keyboard. In this latter case the command
has to be closed by pushing the ENTER button.
• The values having been set in the programming
procedure, can be stored by pushing the STORE
button. Without this, after disconnecting the
PROGRAMMER, these values go lost and the for-
mer values become valid.
SETTING THE OPERATIONAL
PARAMETERS OF THE TV SOUND
MODULATOR
1. Combining the IF signals and adjusting their levels
The vision IF signal (not including the sound car-
rier) of 102 dBmV nominal level on 75 ohms is to be
led to input IF IN on the rear panel. The sound carrier
of the TV MODULATOR must be switched off. With
CW-3000 series TV MODULATORs, this can be done
from the PROGRAMMER: choose the function SCA
(Sound CArrier) in the menu, set its value to 0 then
STORE this setting.
The external IF vision carrier and the internal two
sound carriers will be combined in a directional coupler
within the TV SOUND MODULATOR. In the IF sig-
nal at output IF OUT, the main sound carrier will be
included at -13 dB level and the second sound carrier at
-20 dB, related to the peak value of the vision carrier. In
some cases the user cannot supply the vision IF signal
at its nominal level to the TV SOUND MODULATOR.
If the difference is not more than several dB, both
sound carriers can be adjusted together, using an inter-
nal potentiometer. There is also provision for the indi-
vidual adjustment of the sound carriers for larger differ-
ences of the vision carrier to its nominal value.
These settings should only be made with proper meas-
uring equipment available. In other case please contact
the manufacturer. The locations of the internal adjusting
potentiometers are shown in table 1.
2. C
hoosing the operational mode
The two sound carrier type modulators can be operated
in one of three modes. In the PROGRAMMER menu,
they appear as follows:
SEL (SOUND SELECT)
1 - MONO
2 - STEREO
3 - DUAL SOUND
You only need to key in the proper value and to
STORE it. The STEREO and DUAL SOUND modes
are indicated by separate LEDs in the front plate LED
row.
3. Adjusting the FM deviations
The deviations of the FM channels can be adjusted with
screw-driver potentiometers on the front plate. The
deviations can be read from the LED row with suffi-
cient accuracy. Possible overmodulation (dF ≥35 kHz)
is signalized with a red LED.
4. Options
The CW-3130 TV SOUND MODULATOR (along
with the respective TV MODULATOR) outputs an IF
tv signal with stereo sound according to the B/G-
version German two sound carrier system.
On request, the unit can be delivered in versions for
other two sound carrier systems (6.5/6.26 MHz Czech
system, etc.), too.
GENERAL INFORMATION
In the course of using the unit, the identification of
type number and/or the serial number of the unit may
be required. These data can be read in the sticker on the
unit's bottom side or can be queried by the
PROGRAMMER. To display the type number push F1,
to display the serial number push F2.
The unit needs no particular servicing.
2
CW-3130
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