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The DBI200 is a full capability generator/inserter designed for broadcast video applications and data insertion at the facility output point.
In addition to a solid basic generator/inserter unit, the DBI200 provides loss of program continuity modes, multiple inputs for external data insertion,
VM700T compatible source identification and a text generator for full field and vertical interval message insertion.
The DBI200/VITS200 also provides an eight-field signal insertion sequence for signals such as Ghost Canceller Reference (GCR) signals.
All operating modes and insertion programs may be easily set up from the front panel and saved in nonvolatile memory storage.
Test Signal Generator:
The DBI200 uses 12-Bit, 8 FSC digital test signal generation to ensure test signal accuracy. The test signal complement includes the following:
- NTC7 composite and combination
- FCC composite, multiburst and color bars
- Vertical Interval Reference Signal (VIRS)
- Philips and BTA GCR signals
- Cable multiburst and sweep signals
- (Sin x)/x
- Multipulse
- 10 MHz line sweep
- Red field
- 0 IRE flat field without burst
- These test signals are available as VIT signals and simultaneously and independently as full field test signals
Inserter/deleter functions
The DBI200/VITS200 may be programmed to insert any internally generated signal, external input or the source identification signal on any line from 10 through 23 or 17 through 30 of both fields or in a four-field sequence.
If desired, the same signal or external input may be programmed for insertion on multiple lines. This may be useful in insertion of external data signals.
Four external VITS inputs are provided for insertion of externally generated test and data signals.
All inputs are AC coupled and clamped. The VITS200 assumes the external input signals are locked to the program signal and correctly timed.
Delete and pass functions are available for the same lines as the insert function.
Program Control
Maintaining transparency and continuity of the program channel are prime considerations in the DBI200/VITS200. Distortions and transients are virtually eliminated by
the Tektronix-developed channel switch integrated circuit. Insertion or deletion of VITS can occur only when genlock to the program input signal is attained.
Loss of mains power or genlock causes the program line to be bypassed or a standby condition to be activated.
Program signal delay in operate and bypass is matched.
The DBI200/VITS200 provides for replacement of the program line sync and burst signals with the internally generated sync and burst signals.
This ensures the proper amplitude relationship of the inserted VITS to the sync and burst signals is established prior to inputting the signal to the broadcast transmitter or transmission system.
Timing of the active video to the blanking interval is not affected in the sync and burst regeneration mode.
Text Generator
Should the program input line be interrupted, text may be inserted over the internally generated signal selected as the temporary program line replacement.
The DBI200 internal text generator provides up to three pages of text with a maximum of thirteen lines of 23 characters each per page.
Text insertion of a single line of 23 characters in vertical blanking is available in the normal operating mode. Up to 15 different vertical interval messages may be programmed.
The text generator font set consists of characters and symbols, each a 32x32 pixel array.
Standby Mode
Loss of the program input signal will automatically enable one of three program line output states:
- Program line bypassed
- A user selected external input will be routed to the program line output
- A user selected internally generated signal will be routed to the program line output
Restoration of the program line input signal will terminate the program line continuity action and resume normal operation.
Source identification
The DBI200/VITS200 provides a one line 16-Bit source identification code. The bits may be set in any high/low sequence providing up to 65,536 possible codes. Setting of the code is done with DIP switches accessible through the rear panel.
The identification signal may be placed on any of the available lines in vertical blanking.
The VM700T Video Measurement Set utilizes this signal for identification of sources on displays and printouts of measurement routines.
Remote control:
Ground closure and RS-232 remote control of the following functions is provided::
- Bypass/operate
- Standby mode enable
- Full field message enable
- Full field page select
- Vertical interval message enable
- Vertical interval message select
- Test signal select
Indicator lines for bypass, loss of lock, power on and remote control enabled are provided.
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