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Feature Box
Figure 19
The YUV signal from the PIP module is fed back to the SSB on connector 1682, Pins 6, 8, and 9. This
circuit is called the Feature Box. The Feature Box changes the picture from a 15734 Hz NTSC
interlaced signal to a 480P progressive scan signal at 31468 Hz. The refresh rate or vertical stays
59.94 Hz.
The signal is fed to 7611 on Pins 23, 25, and 26. This IC is called the PICNIC (Picture Improvement
Network IC). The Clamping circuit sets the reference level for the black level of the YUV signal. The
Prefilter circuit limits the higher frequencies to prevent aliasing to low frequencies. The signal is then
fed to a triple Analog to Digital Converter, ADC. The digital signal is then fed to a Time Base
Corrector, a Noise Reduction and Histogram, and to a Multiplexer. The YC/UVC signal is then fed to
the Field Memory IC, 7714. The PROZONIC IC, 7708, then reads the data from 7714. The PICNIC
communicates with the Microprocessor via the I2C buss via the SCL-F and SDA-F lines connected to
Pins 4 and 5. The PICNIC communicates with the PROZONIC via the SN-DA and SN-CL lines. The
EEPROM, 7716, stores operational data for the Microprocessor in the PICNIC.
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