THOMSON VK231PS, Техническое руководство

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CONVERTER 1 AND OUTPUT STAGE
The 5.06-MHz signal is sent to the second input of Converter 1. This converter receives the
4.43-MHz +0.6/-0.8 incident signal at its other input, and outputs two frequencies:
The sum of two frequencies:
5.06 MHz + (4.43 MHz + 0.6/-0.8)
and the difference between two frequencies:
5.06 MHz - (4.43 MHz + 0.6/-0.8)
The difference component, 626,953 kHz -600/+800, is selected by a low pass filter with a cutoff
frequency of 1.4-MHz.
The PAL chroma signal, available on IV001 Pin 14, is sent to the SECAM module. Resistors
RC031 and RC033 set its amplitude. The PAL chroma signal is selected by switch IC101, and
is mixed with the FM luminance signal via TC009.
ME SECAM RECORDING
ME SECAM recording is performed in a similar way to PAL recording. Note, however, that the
phase shifter and the phase detector and put out of operation in this case.
The following frequencies are available at 14 of IV001:
BLUE: 810 kHz +350/-500
RED: 660 kHz -350/+500