Multi-purpose alarm consisting of transmitting, receiving and integrating modules

One-piece inductor

The RF Remote Module is a remote control device that uses radio signals to control various remote devices. After these signals are received by remote receiving devices, they can command or drive various other mechanical or electronic devices to complete each. Kind of operation.
The receiving module has an operating voltage of 5 volts and a quiescent current of 4 mA. It is a super regenerative receiving circuit with a receiving sensitivity of -105 dbm and a receiving antenna of preferably 25 to 30 cm. It is preferably erected. The receiving module itself is not With decoding integrated circuit, so the receiving circuit is only a component, only the application in the specific circuit for secondary development can play its due role.
An integrated circuit is a kind of microelectronic device or component. It uses a certain process to interconnect the components, such as transistors, diodes, resistors, capacitors, and inductors, in a circuit, in a small or small piece of semiconductor. The wafer or dielectric substrate is then packaged in a package to form a micro-structure with the required circuit function; the integrated circuit can be used to assemble the electronic device, and the stable working time of the device can be greatly improved.
The multi-purpose alarm device described in this paper is composed of a miniature radio transmitter and a receiving alarm. It can be widely used for anti-theft and anti-miss of items, and can also be extended for use as a child, mental patient lost alarm, wireless remote control. The doorbell, the primary school sleep awakening device, etc., the radio one-way paging in close range. The device is simple in circuit and easy to manufacture.
The working principle circuit is shown as in Fig. 1, wherein the radio remote control transmitting module A1 and the battery G1 and the power switch SA1 constitute a transmitter; the radio remote control receiving module A2, the analog sound integrated circuit A3 and the like constitute a receiving alarm.
In normal times, the built-in antenna of the A1 module emits an ultra-high frequency modulated electromagnetic wave with a frequency of about 250~300MHz to the surrounding space. It is received by the micro receiving antenna in the A2 module within the effective range of action, and is demodulated, amplified and detected by the internal circuit. After delay and level conversion, the low level is output from the first leg, A3 does not work because the TG pin is at a low level, the triode VT is turned off, and the sounder B does not sound. Once the distance between the transmitter and the transmitter exceeds 15 m, A2 will not receive a sufficient intensity of the transmitted signal, so A2's first foot jumps to a high level, which triggers the A3 internal circuit to work, and repeatedly outputs the stored "叮-咚" acoustic signal through the OUT pin. After the VT power is amplified, the drive B sounds an alarm.
SA2 is a function selection switch. When placed in the "alarm" position, this device can be used for anti-theft, anti-lost, anti-forgotten. When SA2 dials to the "call" position, the A2 foot only receives the A1 transmission. The electromagnetic wave will output a high level (as opposed to the first foot), and trigger A3 to make B sound, so it can be used as a one-way radio paging in close range, such as wireless remote doorbell, sleep wake-up, etc. C1 For the delay capacitor, it can make the A2 state change a little slower, thus enhancing the module's anti-interference ability.
Component selection and production
A1 and A2 select the novel RCM-1A and RCM-1B ultrashort wave radio remote control module kits respectively. This module is a hybrid integrated with high frequency analog circuit, transceiver antenna and digital circuit. The device, its external dimensions and pinout are shown in Figure 2. The module is divided into three types according to the effective control distance: I type (10~15m), type II (20~30m) and type III (35~45m). This production should use I type products.
A3 selects KD-153H type "叮咚" doorbell ASIC chip, and can also use HFC1500 series integrated circuit to store "叮-咚" sound chip directly to replace .B with HC-12 type miniature electromagnetic horn, which is characterized by sound High efficiency and small size. G1 is made up of three SR44 or G13-A button silver oxide micro batteries in series. G2 is made up of three 5th dry batteries in series. If you want to further reduce the volume, you can also use 7th battery or SR44. Type button miniature battery.
The transmitter circuit is soldered in a plastic case of the size of a matchbox, and a nylon rope with a length of about 60 cm is attached for easy use. The receiving alarm circuit is soldered in the plastic BP casing for the user to carry. Carrying. This circuit can be put into use without debugging. The actual working current of the transmitter is only about 1.2mA, and the static waiting current of the receiving alarm is only about 0.8mA.