This document summarizes a color TV pattern generator. It outputs predetermined video waveforms and synchronization signals used to test TV sets. The output contains horizontal and vertical sync pulses and, for composite video generators, a colorburst signal. The video signal contains luminance, chrominance, and synchronization components. A circuit diagram shows a single IC can generate standard patterns using Schmitt inverters. Patterns are used for color settings, geometry adjustments, and more. Variants include generators from Phillips, Grundig, and others known for their pattern cards.

1. Color TV
Pattern
Generator
BY
SHASHWAT REVDANDEKAR
SAMARTH SHARMA
BICHITRA PATRA

2. Description
It is signal generator which outputs predetermined video waveforms.
It also gives the various signals used in synchronization of television devices.
The pattern generator is useful for finding faults in TV sets.
Irrespective of the specific type the output of a video generator will usually contain synchronization
signals like the horizontal sync and vertical sync pulses (in analog).
The Composite Video Signal Generators will also include a colorburst signal in the output along with
the above mentioned output signals

3. Structure of a video signal
The video carrier signal is demodulated to give a composite video signal(as shown in figure-1).
This output signal has 3 basic signals:
Luminance Signal(brightness)
Chrominance Signal(color)
Synchronization Signals
The monochrome signal is similar to the color one except the Color Burst and Chrominance Signal (as
shown in figure-1) are not present

4. Figure-1: A typical composite video signal

5. Figure-2: Circuit diagram of single IC TV pattern generator
The circuit uses Hex Schmitt Inverter IC CD40106

6. Features
Auto generated composite video signal
Standard & stable colour composite video signal
14 standard patterns
Check pattern
Horizontal bar pattern

7. Uses
In general the pattern generator is used to find faults in television sets; some standard patterns used to test
are as follows:
Patterns provide video and RF modulated signals for alignment
Colour bars are used to color settings
Horizontal line, vertical line and circle patterns are used for Raster, Geometric and Linear adjustments
White pattern is used for white balancing
Apart from this it is used for educational purposes

8. Variants
Even though there are a lot of tv pattern generators available readily, there are some generators
whose generated pattern cards are widely popular
Phillips (PM 5540, PM5544, PM 5644)
Grundig VG 1001(FuBk)
SMPTE (Color Bars)
Snell and Wilcox (Zone Plate)

9. Phillips PM5540
Some of the widely popular test cards
Phillips PM5544 SMPTE Color Bars

10. Thank You!