BE-3110
24
4.6 Adjusting the Scramble Timing
1. Connect the devices as shown in Connection Diagram 5.
2. Set the devices as shown below.
¶
Video SG
All black signals
¶
TV modulator
IFv: 45.75 MHz/50 dBmV
IFa: 41.25 MHz/45 dBmV
¶
Oscilloscope
H: 1
µ
s/div
V: 0.1 V/div
¶
CATV terminal
US-7ch/10 dBmV input
¶
Variable resistance attenuator
Adjust the output level to 10 dBmV
3. Set this unit to the adjustment (Digitally SW:F) mode.
4. Set to the group 0 mode 1 using the key switch on the front
panel of this unit, and adjust so that the return waveform of the
video signal in the timing waveform (Fig. 4-7) shown on the
oscilloscope screen comes to point
1
.
5. Set to the group 0 mode 2 using the key switch on the front
panel of this unit, and adjust so that the compressed waveform
of the video signal in the timing waveform shown on the
oscilloscope screen comes to point
2
.
Note 8 :
Steps 4, and 5 can be performed in any order.
Fig. 4-7 Timing Waveform
Fig. 4-8 Connection Diagram 5
1
µ
s
2
µ
s
1
2
H:1
µ
s/div
V:0.1V/div
CW
generator
115K
TV modulator
BE-3110
TV
demodulator
Oscilloscope
VHF
AMP
CATV
terminal
Variable
resistance
attenuator
Video
SG
Video out
38.9MHz
Video in
RF out
RF in
MIXER
US-7ch
US-3ch
10dBmV
100.15MHz
H-sync
All black signal
TRG.
Video out
IFa in
IFa out
IFv in
IFv out
Video in
IFa out
IFa in
IFv out
IFv in
TV
IF
MOD
RF
CONV.
