Abstract: A radio communication apparatus has a switch for indicating occurrence of emergency, a speaker, a speaker driver for emitting an alarm sound by driving said speaker in response to the operation of the switch, and a transmitter for transmitting a predetermined alarm signal by radio. When an emergency condition occurs to an owner of the radio communication apparatus, the radio communication apparatus emits an alarm sound from the speaker and emits an alarm signal by radio in response to a switching operation. Therefore, a person a short-distance away will be informed of an emergency by sound, and a person a long-distance away will be received by using a radio.
Abstract: A radio communication apparatus has a switch for indicating occurrence of emergency, a speaker, a speaker driver for emitting an alarm sound by driving said speaker in response to the operation of the switch, and a transmitter for transmitting a predetermined alarm signal by radio. When an emergency condition occurs to an owner of the radio communication apparatus, the radio communication apparatus emits an alarm sound from the speaker and emits an alarm signal by radio in response to a switching operation. Therefore, a person a short-distance away will be informed of an emergency by sound, and a person a long-distance away will be received by using a radio.
Abstract: An antenna that comprises a rod, a movable coil, and a holding section which holds the movable coil in a manner that allows the movable coil to slide in and out of the holding section. When the movable coil is drawn into the holding section, the holding section tunes to a particular desired frequencies in the upper portion of the VHF band and the UHF band; for example, 144 MHz and 430 MHz. When the movable coil is out of the holding section, the holding section, the rod, and the portion of the movable coil outside the holding section form antenna element of a center-loading type that tunes to frequencies in the HF band and the lower portion of the VHF band; for example, frequencies in the range of 3MHz to 50MHz. The tuning frequency is varied by sliding the position of the coil.
Abstract: An electronic device (21) switches its operation mode in accordance with the type of an installed battery pack (22). The battery pack (22) has a regulator (222), a specification-discriminating terminal (TJ), and a resistor (224), connected between the regulator (222) and the specification-discriminating terminal (TJ) and having a resistance corresponding to the specification of the incorporated battery (221). The electronic device (21) has a monitor resistor (214) connected between a terminal (TL) connected to the specification-discriminating terminal (TJ) of the battery pack (22) and ground, a discriminating circuit (212, 215, 216) for detecting a monitor voltage generated across this monitor resistor (214) to discriminate the specification of the battery (221), and a switch controller (212, 219) for switching the operation mode in accordance with the specification discriminated by the discriminating circuit (212, 215, 216).
Abstract: The invention relates to a superheterodyne circuit characterized by comprising a first mixer converting a received signal into the first intermediate frequency, a second mixer converting the first intermediate frequency into a second intermediate frequency, and a product detection stage demodulating the second intermediate frequency to an audio frequency, by having a constitution wherein the local oscillation of the first mixer is input from a VCO for which a PLL circuit is used, wherein the local oscillation of the second mixer is an output obtained by mixing the frequency of a second oscillator with that of a third oscillator in a fourth mixer, wherein the second oscillator combined with the frequency of the VFO in the sixth mixer, alone or in further combination with the frequency of the output of a BFO input via to the product detection stage is the frequency of the third oscillator or an output obtained by mixing the frequency of the third oscillator with a frequency obtained through the frequency divisi