JVC 330 Service Manual

Contents

Chapter 2—Functional Descriptions2-32 Model 330. 340SC, and 370SC Service ManualSystem Power SupplyInputs Description+48V Power for horizontal deflection+15V Power for the analog section of the HDB-15V Power for the analog section of the HDB+5V Power for the digital devices on the HDBGND Return for HDBInterlocks and ProtectionInputNoneOutputHSENSRED - Used to shut down the CRT beams in the event of horizontal sweepfailure.HSENSGRN - Identical to HSENSERED.HSENSBLU - Identical to HSENSERED.Internal+INLCKPrevents the horizontal output section from being turned on when 1 or moredeflection coils not connected.-INLCK! Part of +INLCK circuit.! Minimum Frequency on Oscillators and PLLs! Ensures that there will be a sweep in both the horizontal and verticaldirections when the sync pulse disappears. This is for protection of the CRTphosphor.Vertical Deflection Board P/N 102521(VDB)The Vertical Deflection Board plugs into the electronics card cage and is the secondboard from the front in the card cage.The following functions are provided by the VDB:Drive main vertical deflection coils to provide vertical raster scan forall three (3) CRTs.Drive all correction coils to provide convergence and geometrycorrection.Scan failure detection for all six main deflection circuits.Vertical size adjustment.Vertical linearity adjustment.