JF24D wireless bidirectional module integrates the functions of high frequency keying (GFSK) transceiver circuit, and realizes the function of high-speed data transmission with extremely small volume and low cost. The transmission rate of the upgraded version of JF24D can be 2M, 1M and 250K, which is increased from the original 87 to 128, and it can realize stable and reliable short-distance data transmission in the crowded ISM frequency band without mutual interference. JF24D works in the ISM frequency band which is open all over the world, and it does not need a license.
As shown in the figure;
English-English translation
Radio frequency wireless module
Application area
Radio frequency module transmission is widely used in vehicle monitoring, remote control, telemetry, small wireless network, wireless meter reading, access control system, cell paging, industrial data acquisition system, wireless tag, identity recognition, contactless radio frequency smart card, small wireless data terminal, safety fire prevention system, wireless remote control system, biological signal acquisition, hydrometeorological monitoring, robot control, wireless 232 data communication, wireless 485/422 data communication, digital.
Mould module
Transmitting module
Launching module F05R of Anyang New Century Institute of Electronics
Main technical indicators:
1. communication mode: AM
2. Operating frequency: 3 15MHz/433MHz.
3. Frequency stability: 75KHz
4. Transmitting power: 8dBm
5. Static current: ≤0. 1uA
6. Emission current: 3 ~ 50mA
7. Working voltage: dc2.1~ 3.5v.
The working frequency of data transmission module is 3 15MHz, and SAW resonator is used to stabilize the frequency, which is extremely stable. When the ambient temperature changes between -25 and +85 degrees, the frequency drift is only 3ppm/ degree. Especially suitable for wireless remote control and data transmission system. The frequency stability of acoustic resonator is second only to crystal, but the frequency stability and consistency of general LC oscillator are poor. Even if high-quality fine tuning capacitors are used, it is difficult to ensure that the tuned frequency points will not shift due to temperature difference and vibration.
There is no coding integrated circuit in the transmitter module, but a data modulation transistor Q 1 is added. This structure is convenient to interface with other fixed coding circuits, rolling coding circuits and single chip microcomputer, regardless of the working voltage and output amplitude signal value of the coding circuit. For example, when a coded integrated circuit such as PT2262 or SM5262 is used, its data output terminal pin 17 is directly connected to the input terminal of the data module.
The working voltage range of the data module is wide, which is 2.1~ 3.5v. When the voltage changes, the transmitting frequency is basically unchanged, and the receiving module matched with the transmitting module can receive stably without any adjustment. When the transmission voltage is 3V, the transmission distance in the open area is about 20 ~ 50m, and the transmission power is relatively small, about 100 ~ 200m at 5V, and about 300 ~ 500m at 9V. When the transmission voltage is 12V, it is the best working voltage, and the transmission effect is good. The transmission current is about 60mA, and the transmission distance in the open area is 700. When the voltage is greater than l2V, the power consumption increases, and the effective transmission power is no longer significantly improved. This module is characterized by relatively large transmission power and long transmission distance, which is more suitable for communication under harsh conditions. It is best to choose a conductor with a length of 25 cm for the antenna, and it is best to stand when transmitting at a long distance. Due to the influence of many factors when transmitting radio signals, the actual distance is generally only half or even less than the nominal distance, which should be paid attention to when developing.
The data module is modulated by ASK to reduce power consumption. When the data signal stops, the transmitting current drops to zero, and the data signal can be directly connected to the input end of the transmitting module through a resistor instead of a capacitor, otherwise the transmitting module cannot work normally. The data level should be close to the actual working voltage of the data module to obtain high modulation effect.
It is best to install the transmitting module vertically on the edge of the motherboard and keep a distance of more than 5mm from the surrounding equipment to avoid being affected by the distribution parameters. The transmission distance of the module is related to the frequency and amplitude of the modulation signal, the transmitting voltage and battery capacity, the sensitivity of the transmitting antenna and receiver, and the transceiver environment. Generally speaking, the maximum transmission distance in an open area is about 800 meters. When encountering obstacles, the distance will be shortened. Due to the refraction and reflection in the process of radio signal transmission, some blind areas and unstable areas will be formed, and different transmitting and receiving environments will have different transmitting and receiving distances.
Super regenerative receiving module
Anyang New Century Electronic Module Institute J04U
Volume of super regenerative receiving module: 23x 13x5.
Main technical indicators:
1. communication mode: AM
2. Operating frequency: 3 15MHZ/433MHZ.
3. Frequency stability: 200KHZ
4. Receiving sensitivity:-95DBM
5. Static current: ≤5MA
6. Working current: ≤0.3MA
7. Working voltage: DC2.6-3.5V
8. Output mode: TTL level
The working voltage of the receiving module is 3 volts, which is a super regenerative receiving circuit with a receiving sensitivity of-95dbm. The receiving antenna is preferably a line of 25-30 cm, and it is preferably upright. The receiving module itself has no decoding integrated circuit, so the receiving circuit is only a component, and only when it is applied to a specific circuit for secondary development can it play its due role. This design has many advantages, and can be used in conjunction with various decoding circuits or single chip microcomputer, so the design circuit is flexible and convenient.
The advantages of this circuit are:
1, the antenna input has a frequency selection circuit, which does not depend on the frequency selection function of 1/4 wavelength antenna. When the control distance is very close, the external antenna can be shortened or even removed.
2. The waveform at the output end is relatively clean when there is no signal, and the interference signal is short needle pulse, unlike other super regenerative receiving circuits, which will produce dense noise waveform, so it has strong anti-interference ability.
3. The radiation of the module itself is very small, and the shielding effect of the reticular grounding copper foil on the back of the circuit module can reduce the leakage of its own oscillation and the intrusion of external interference signals.
4. The copper core inductor with skeleton is used for sealing after the frequency is adjusted to 3 15M. Compared with the circuit with adjustable capacitor to adjust the receiving frequency, the stability of temperature and humidity and the ability of resisting mechanical vibration are greatly improved. The adjustment precision of adjustable capacitor is low, and the adjustment range is only 3/4 turns, while adjustable inductor can realize multi-turn adjustment. The adjustable capacitor cannot be sealed after adjustment, because the approach or intrusion of various media, whether conductor or insulator, will change the capacitance of the capacitor and then affect the receiving frequency. In addition, when the unsealed adjustable capacitor vibrates, there is displacement between the stator and the rotor; When the temperature changes, thermal expansion and cold contraction will change the distance between stator and rotor; The change of humidity changes the capacity due to the change of medium; Working in humid environment for a long time will also change the capacity because of the oxidation of stator and rotor, which will seriously affect the stability of receiving frequency. Adjustable inductance can solve these problems, because the inductance can be sealed after adjustment, and the insulator sealant will not change the inductance.
Superheterodyne receiving module
Anyang New Century Institute of Electronic Technology Module J05E
Volume of superheterodyne receiving module: 35x 13x8.
Main technical indicators:
1. communication mode: AM
2. Working frequency: 316.8mhz.
3. Frequency stability: 75KHZ
4. Receiving sensitivity:-102DBM
5. Static current: ≤5MA
6. Working current: ≤5MA
7. Working voltage: DC 5V
8. Output mode: TTL level
The superheterodyne receiving module provided here adopts imported high-performance wireless remote control and data transmission ASIC RX33 10A and 3 16.8M acoustic resonator, which is stable and reliable and suitable for all-weather operation in harsh environment.
Introduction of RX33 10A integrated circuit;
RX33 10A is a wireless remote control and digital signal receiving integrated circuit produced by HMARK Company in Taiwan Province Province, which is specially used for AM-keying ASK modulation. It includes low noise high frequency amplifier, mixer, local oscillator, intermediate frequency amplifier, intermediate frequency filter, comparator and so on. It is a primary frequency conversion superheterodyne circuit, which is packaged in a double-row 18 pin wide chip. The main technical indicators are as follows:
Operating frequency: 150 ~ 450 MHz
Working voltage: 2.7 ~ 6V
Working current: 2.6 mA (under 3V power supply)
Receiving sensitivity:-105 DBM (1K data rate and antenna matching)
Maximum data rate: 9.6KBPS
The signal received from the external antenna is coupled to the frequency selection network composed of L3 and C9 to C8, and then input to the input end 14 of the internal high-frequency amplifier of RX33 10. The high-frequency amplified signal in the chip (the gain is 15 ~ 20 dB) is mixed with the local oscillator signal (3 16.8M) by a mixer to generate1.8m.
The superheterodyne receiver requires high impedance matching of the antenna, and the impedance of the external antenna must be 50 ohms, otherwise it will have a great influence on the receiving sensitivity. Therefore, when using the common wire with the wavelength of 1/4, it should be 23 cm, so as to minimize the lead length from the antenna root to the antenna welding point of the transmitting module. If it can't be lowered, it can be connected by RF coaxial cable with characteristic impedance of 50 ohms (there is a special grounding solder joint on the right side of antenna solder joint).
Performance difference between RF super regenerative receiver and superheterodyne receiver
Superregenerative and superheterodyne circuits have their own advantages and disadvantages. Super regenerative receiver is cheap, economical and has high receiving sensitivity, but its disadvantages are obvious, such as large frequency drift with temperature and poor anti-interference ability. The superheterodyne receiver has the advantages of stable frequency, strong anti-interference ability and stable performance with single chip microcomputer. The disadvantage is that the sensitivity is lower than that of super-regenerative receiver, and the price is much higher than that of super-regenerative receiver, and the strong short-range signal may be blocked.