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The IO-4, IO-5 control-lines select the sync-inputs of the
HEF4052 (7102.)
In our figure, these control-lines are named SYNC SELECT 2
and SYNC SELECT 1.
Via IO-6 line (called TRISTATE SYNC), the sync output can be
put in tri-state.
9.6.5
Control Function
The different selections are made by the I/O expander,
2
controlled by I
C.
These selections can be made with the user interface.
9.6.6
Audio
Audio left and audio right are connected via the two cinches
and passed through the module.
9.7
Video: High-end Input Processor (HIP,
Diagram B2)
The HIP TDA932xH contains the following functions:
•
IF demodulation.
•
AFC signal generation, used to track drifting transmitters.
•
Sound carrier re-generation (SIF.)
•
Sync acquisition, delivering H
9.7.1
Inputs
The HIP has various inputs:
•
Full matrix switch with:
–
Two CVBS inputs.
–
Two Y/C (or additional CVBS) inputs.
–
One CVBS front-end input.
•
Two RGB inputs.
9.7.2
Outputs
One can select three separate, switchable outputs:
•
One YUV-output, which is fed to the PICNIC.
•
Two CVBS outputs, one for CC-decoding (CVBS-TXT) and
the other for MONITOR out to have WYSWYR (What you
see is what you record.)
9.7.3
Video Processing
The HOP will generate synchronization signals derived from
the feature box (PICNIC, pin 60 and 61) signals.
If a VCR is connected, there is also an automatic correction for
®
MacroVision
. This is active for the external sources.
The HIP itself (no external voltage) controls the Y/C switch in
the HIP.
The chrominance decoder in the HIP is full multi-standard:
NTSC/PAL/SECAM, but only NTSC is decoded.
The crystal can be connected without any alignment. The
crystal is also used as a reference for the synchronization. A
digital control circuit that is locked to the reference signal of the
color decoder determines the start-up of the sync.
Note: If the crystal must be replaced, you must use only the
genuine replacement part. This crystal is very precise: if it is
replaced by another type of crystal, there may be no color,
because of a different capacity.
A sync separation circuit is integrated in the HIP; the HIP
delivers the H
and V
A50
Circuit Descriptions and Abbreviation List
and V
.
A,
A
to the PICNIC and DW-panel.
A50
EM5A NTSC
9.8
Video: Feature Box 7 (Diagram B3A, B3B, and
B3C)
The objective for this chassis is to reach a sharper picture by
means of a higher definition. This is achieved via the 'Pixel
Plus' feature. So what exactly is Pixel Plus?
9.8.1
Introduction
The basic function of the Feature box (FBX) is picture
improvement, and depending on the version, several scan
conversion methods are possible. The PICNIC (SAA4978H) is
the central key component.
The feature box is integrated on the SSB.
In the Feature Box 7 (FBX7), a new IC is used, called the
'Eagle.' This IC performs the following picture improvements:
•
Horizontal: increases pixels per line from 840 to 1680 (the
number of pixels per line is doubled.) This, by itself, does
not mean an improvement in definition. To achieve that, the
new pixels are digitally processed inside the Eagle with
Luminance Transient Improvement (LTI) and Peaking.
This will give the new pixels extra picture information,
which results in steeper slopes and contrast improvement
in details.
•
Vertical: increases from 525p lines to 1050i lines. Also,
those new lines are processed inside the Eagle with LTI
and Peaking, again resulting in lines with extra picture
information.
•
The line frequency is fixed on 2 fH and the frame
frequency at 60 Hz. In addition, other modes, like 'Digital
Scan' are still possible.
•
The color enhancement features of the TOPIC are
performed by the Eagle.
9.
EN 125
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