NTSC-TV原理
Chapter 1. NTSC Introduction
Raster Scan Deflection Waveforms
Figure shows Horizontal & Vertical Sweep Voltage Waveforms, and their relative timing Relationships
Interlace Raster Scan Illustration of scanning beam on CRT face during Interlace scan.
Interlaced Scan
Illustration of how Interlacing is accompolished.
Raster Scan Synchronization Waveforms
NTSC/RS-170A, complete set of waveforms, including Composite Blanking.
Note Color Subcarrier phasing (in red).
Horizontal Sync Complex
Illustrating "Front Porch," "Sync Tip," "Back Porch" with Color Burst riding on it.
The interval between the end of the sync tip & the start of the burst is sometimes refered to as the "Breeze -way." Note also, the "Burst Flag" (D.C. Restore clamp).
Vertical Sync Recovery
Vertical sync recovery by Integration of composite sync waveform.
So-called "Hammerhead" waveform
Normally invisible waveform of the "Vertical Interval," showing the relationship of the Horizontal sync Pulses;
Pre-Equalization Pulses; Serration Pulses; Post-Equalization Pulses; Color Burst, etc.
Sync Seperator
Circuit for the recovery of both, Horizontal Sync & Vertical Sync, as well as, Even/Odd Field Flag.
Sync Seperator
Sync Separator with "Noise" pulse suppression--used in terrestrial receivers & VTR/VCRs.
Horizontal Deflection
Horizontal deflection circuit, showing Drive transistor, Damper diode, Deflection Coil, Resonating & linearizing Capacitors; with High Voltage Fly-back transformer (tuned to third harmonic of scanning
frequency).
Horiz Deflection Sequence
"L" & "C" Charge Discharge sequencing related to horizontal scan beam position.
Numerical Relationships
Phase Locked Loop (PLL)
Broadcast Spectrum Shaping
NTSC Broadcast signal uses Vestigial SideBand (VSB) transmission, with properly bandlimited "I" & "Q" chroma information.
Note also, the aural carrier @ 4.5 MHz. In practice, this is inserted as a highlevel aural transmitter output at the transmitting antenna