PAL-M

PAL-M is the analog color TV system used only in Brazil, where color broadcasts began on 19 February 1972, making Brazil the first South American country to introduce color television. What sets PAL-M apart from every other analog TV system is its combination of the 525-line, 29.97 frames-per-second System M with the PAL color encoding method, using a color subcarrier frequency very close to that of NTSC. Elsewhere, PAL and SECAM are paired with 625-line systems, and NTSC with 525-line systems.

Origins

The first color transmission occurred on 19 February 1972, when TV Difusora in Caxias do Sul, working with TV Rio, broadcast the Caxias do Sul Grape Festival. Most programs did not fully switch from black and white to color until 1978, and color only became common nationwide by 1980. Since NTSC was the natural match for countries using the monochrome System M, Brazil’s choice of PAL created hardware incompatibility issues and required new television sets and production equipment.

Walter Bruch, PAL’s inventor, attributed Brazil’s decision to an advertising campaign by Telefunken and Philips across South America in 1972. This campaign included color test broadcasts of popular shows with TV Globo and technical demonstrations for TV station executives. PAL-M signals are generally identical to North American NTSC signals except for the color carrier encoding. Both are based on the monochrome CCIR System M standard, so PAL-M displays in monochrome with sound on an NTSC set, and vice versa.

Technical specifications

However, gray tones are incorrect because of different gamma correction values (2.2 for NTSC, 2.8 for PAL-M). PAL-M is incompatible with 625-line PAL versions due to differences in frame rate, scan lines, color subcarrier, and sound carrier. On a European PAL television, it typically produces a rolling or squashed monochrome picture with no sound, just as NTSC does. PAL-M details: - Transmission band: VHF/UHF - Frame rate: 30/1.001 Hz ≈ 29.97 Hz - Field rate: 60/1.001 Hz ≈ 59.94 Hz - Scan lines: 525 - Active lines: 480 - Channel bandwidth: 6 MHz - Video bandwidth: 4.2 MHz - Vision/sound carrier spacing: 4.5 MHz - Color subcarrier: 8181/2288 MHz ≈ 3.575611 MHz - Assumed receiver gamma: 2.8 - Color model: YUV PAL-M colorimetry is indicated on BT.470-6 and similar to the original 1953 color NTSC specification.