PAL-NTSC-SECAM standard converter for inter-country transmissions - increases colour amplitude before conversion and reduces it again later

摘要

The PAL/NTSC-SECAM standard converter, for transmission between countries using different tv standards, increases the amplitude of signals having low colour saturation to a higher level of colour saturation before the actual standard conversion process takes place. After the conversion is complete the amplitude is reduced by the same amount as it was increased earlier. Raising and lowering the amplitude in this way improves the quality from the FBAS signal and changed-over to a carrier frequency suitable for the conversion, it is passed to a first gain-controlled amplifier, and after conversion and extraction of the reference signal it is passed to a second gain-controlled amplifier.