CIRCUIT DESCRIPTION | Appendix |
B.REC mode
a)Luminance Signal Processing
The signal is to pin 38,34 of ICY01, and one is selected to input to AGC AMP.
This input signal performs sync AGC and peak AGC.
And then , it is input to the 6dB divider where its level is educed to 0.5V.
LPF and 1H Delay separates luminance signal from output signal of the divider. The separated luminance signal is passed through pin 21, and it is input to pin 20.
The level is clamped in clamp circuit which fixes sync tip to a specific DC level in order to prevent Frequency drift while video signal is converted to FM signal.
The edge of the signal is emphasized by Detail Enhancer.
The emphasized signal is supplied to
which means that amount of emphasis is dependent on the input level, for instance, the lower input level, the large amount of emphasis.
Main emphasis emphasizes the high frequency of the adjusted signal again.
White/Dark clip is conducted in order to prevent the luminance signal from undershooting and overshooting which are occurred during the above emphasize process.
The luminance signal modulated by FM modulator is passed through
It is supplied to AGC Amp of
b) Color Signal Process
The video signal input from pin 38,34 of ICY01 is passed through AGC AMP and BPF.
A color signal separated by 4.43MHz BPF.
This signal is supplied to Comb Filter, and separated color signal.
Then the signal goes to ACC section which automatically controls color burs level.
After Burst Emphasis boots burst signal 6dB, 4.43MHz carrier frequency is input to Main converter and mixed with 5.06MHz carrier frequency from
In the long run, the output is 5.06MHz 6 4.43MHz.
The
The output signal is mixed with modulated
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