Samsung DVD-V5450, Service Manual

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Circuit Operating Descriptions
13-30 Samsung Electronics
14) Hold Pulse
It makes standard signal(Pulse) to compensate SW noise.
15) DET(Hi-Fi/LINEAR)
From the Hi-Fi envelope inputed from pre-amp,it decides whether the signal passing through L-CH BPF is
Hi-Fi or LINEAR tape it’s size(the signal passing through BPF is below 10mVpp, it is not Hi-Fi, therefore, it
output linear)
16) DOC(Drop Out Compensation)
If demodulation is conducted without properly treating the damage on Hi-Fi envelope caused by scratch on
the tape,noise occurs.
In order to improve this noise occurrence, DO DET compensate the drop-out using the same methode of
compensating the switching noise when the damage on the envelope ranges 10~15mVpp.
17) ENV DET
To obtain optimal tracking,envelop must be peak to peak and micom should be in DC. It is a function to
convert Hi-Fi envelop to DC. If it is lower than 0.8V at micom,it sends linear mode date to HiFi IC.
18) Serial Data Decoder
It receives I2C BUS to enable the operation of inner block and decodes into serial data.