Vits 200 And Asg 100/Asg140 Audio/Video Measurement; Operating Instructions - Tektronix VM700T User Manual

VITS 200 and
ASG100/ASG140
Audio/Video Measurement

Operating Instructions

VM700T Option 40/41/42 Audio Measurements User Manual
The Video/Audio Synchronization custom modification turns the test signal text
of the VITS 200 Generator and Inserter and the output of the ASG100 or
ASG140 Audio Generator on and off at the same instant in time.
ASG 100/ASG 140 Instructions
1. Select manual mode.
2. Set frequency for 10 kHz.
3. Set output level to –10 dB.
4. Select (Red LED is on).
Checkout. Grounding pin 1 of the remote connector turns off the audio output.
VITS 200 Instructions
This procedure is used to place the signal in the vertical interval.
1. Connect a NTSC video source so that the VITS 200 is genlocked.
2. From the front panel, select:
3. Input the message you intend to use.
4. Connect a special cable between the VITS 200 remote connector and the
ASG100 remote connector as shown in Figure 2–20.
Checkout. When the VITS 200 is genlocked, the signal at pin 20 of the remote
connector will be a TTL HIGH voltage for 4.5 seconds, and then LOW for
0.5 seconds. The signal transitions from high to low at line 262 field 3. The
audio output is turned ON at this time, but the text inserted by the VITS 200
does not appear until field 1 line 11. The VM700T Audio/Video Timing
measurement removes this delay time before presenting the measured time
difference.
NOTE. The wiring diagram in Figure 2–20 selects message number 2 by
grounding pin 2. You can select any of the 15 possible messages by grounding
different selection lines (pin 2, 3, 4, or 5).
Option 41 and Option 42
2–35