Abstract: An AGC circuit comprises an AGC filter, a hum detection circuit, and a time constant control circuit. The hum detection circuit detects a hum component included in an AGC signal. The time constant control circuit automatically controls the time constant of the AGC filter in accordance with the level of a detected hum component in such a manner that when the level of the hum component is large, the time constant of the AGC filter is varied to be small, while when the level of the hum component is small, the time constant of the AGC filter is varied to be large. Thus, the AGC filter outputs an AGC signal from which a noise component, particularly a hum component, is eliminated on the basis of a time constant determined by the time constant control circuit, so an AGC is carried out without the influence of the noise component included in the AGC signal.

Abstract: A CATV terminal, which has a timer function capable of supplying power to the CATV terminal at a user-programmed time, tuning-in to a user-programmed channel, and stopping the supply of power at a user-programmed time, is used to control an external apparatus such as a VCR or a TV receiver. Remote-control codes, corresponding to functions of the external apparatus, are stored in the CATV terminal ROM. These codes are read out of the ROM, decoded, and sent to the remote-control signal receiving element of the external apparatus. Therefore, the external apparatus is controlled by the CATV terminal using the remote-control codes of the external apparatus.

Abstract: Apparatus for the distillation of sea water and desulfurization has a vessel directly contacting waste gases exhausting from a boiler with sea water for absorbing sulfur oxides contained within the waste gases, an oxidation device to convert the sulfites that are produced by absorption of the sulfur oxide into sulfates through a catalytic action of metallic ions in the sea water, a decarbonization device, a deaerator, and a heating type distillation apparatus that uses the sea water used for the desulfurization as supplementary water. The oxidation, desulfurization and the separation of air are processes conducted continuously.

Abstract: A waste flue gas desulfurizing method in which a waste flue gas containing sulfurous acid gas is contacted directly with sea-water, whereby the sulfurous acid gas is absorbed in the sea-water and concurrently sulfites are formed in the sea-water by the reaction between the sulfurous acid ions and metal ions present in the sea-water, and then the carbonic acid component contained in the sea-water which is then in the acidic region is released therefrom by a decarbonation operation to restore the pH value of the sea-water in the neutral region, and thereafter oxygen contained in air or from other source is introduced into the sulfite-containing sea-water to convert said sulfites into sulfates.