PLL 1 Watt FM transmitterPLL 1 Watt FM transmitter - 2PLL 1 Watt FM transmitter - 3
Description: This small FM transmitter includes a limiter, a microphone amplifier, and a PLL digital tuning. All the parts are placed on one circuit board. The RF power is switchable between 1 W (HI) and 0.2 W (LO). Technical specifications: Supply voltage: 12 V from accumulator or regulated power supply. Supply current (HI/LO): 270/170 mA. RF power HI: 1 W. RF power LO: 0.2 W. Impedance: 50-75 ohm. Frequency range: 87.5-108 MHz. Modulation type: wide-band FM. Modulation inputs: line, mic, RDS/MPX. PCB dimensions: 11.3 x 8.8 cm. The schematic diagram is divided into three parts: RF part (numbered from 1), PLL (numbered from 30), and audio part (numbered from 50). Connect a 6 V / 0.1 A bulb to the output and set the right frequency on PLL. Set the RF power to HI. Now turn on the transmitter. You should tune it on a receiver. Maybe you might stretch coils of the L1. Fix the L1 in position when the tuning voltage (on Q3) is in the range of 4-9 V. Then use C15, C16, and C17 to adjust the highest power (the highest light of the bulb). Then you can connect the antenna and audio signal. Adjust R1 until the audio sounds as loud as the other stations. Complete parts list.
This FM transmitter circuit is designed to provide a compact and efficient means of transmitting audio signals over a short range. The device operates in the FM frequency range of 87.5 to 108 MHz, making it suitable for personal broadcasting applications. The power output can be adjusted between two levels, 1 W for higher range and 0.2 W for lower range, allowing flexibility depending on the application and regulatory requirements.
The circuit is structured into three main sections: the RF section, the Phase-Locked Loop (PLL) section, and the audio section. The RF section is responsible for generating the radio frequency signal, utilizing components such as transistors and capacitors to create stable oscillations at the desired frequency. The PLL section ensures that the transmitter can lock onto a specific frequency, providing precise tuning capabilities. This is particularly important for minimizing interference with other radio stations and ensuring clear audio transmission.
The audio section includes a microphone amplifier and modulation circuitry, allowing for the input of audio signals from various sources, including microphones and line inputs. The modulation type used is wide-band FM, which provides better sound quality and less distortion compared to narrow-band FM.
The circuit board is designed to accommodate all components in a compact layout, with dimensions of 11.3 x 8.8 cm. The use of a 12 V power supply, either from an accumulator or a regulated source, ensures adequate power for operation, with current consumption varying based on the selected RF power output.
For assembly, the parts list includes a variety of resistors, capacitors, and semiconductors, each selected for their specific roles within the circuit. Notably, the use of trimmer capacitors allows for fine-tuning of the circuit parameters, ensuring optimal performance. The inclusion of connectors for audio input, antenna connection, and power supply facilitates ease of use and integration into various setups.
Overall, this FM transmitter circuit provides a comprehensive solution for personal audio broadcasting, combining essential features in a compact design suitable for hobbyists and engineers alike.This small FM transmitter includes a limiter, a microphone amplifier and a PLL digital tuning. All the parts are placed on one circuit board. The RF power is switchable between 1 W (HI) and 0,2 W (LO). Technical specifications: Supply voltage: 12 V from accumulator or regulated power supply. Supply current (HI/LO): 270/170 mA. RF power HI: 1 W. RF power LO: 0,2 W. Impedance: 50-75 ohm. Frequency range: 87,5-108 MHz. Modulation type: wide-band FM. Modulation inputs: line, mic, RDS/MPX. PCB dimensions: 11,3 x 8,8 cm. The schematic diagram is divided into three parts: RF part (numbered from 1), PLL (numbered from 30) and audio part (numbered from 50). Connect a 6 V / 0,1 A bulb to the output and set the right frequency on PLL. Set the RF power to HI. Now turn on the transmitter. You should tune it on a receiver. Maybe you might stretch coils of the L1. Fix the L1 in position when the tuning voltage (on Q3) is in range 4-9 V. Then use C15, C16 and C17 to adjust the highest power (the highest light of the bulb). Then you can connect antenna and audio signal. Adjust R1 until the audio sounds as loud as the other stations. Complete parts list
Resistors:
1x 10
1x 47
1x 100
1x 270
2x 220
3x 470
1x 820
5x 1k
1x 1,5 k
1x 4,7 k
9x 10 k
3x 22 k
3x 27 k
1x 56 k
1x 47 k
1x 180 k
1x 240 k
1x 10 M
3x pot.
This is a high-fidelity stereo PLL FM transmitter designed for various audio sources including computers, sound cards, game consoles, CDs, DVDs, MP3 players, and stereo mixers. The board features two microphone amplifiers, enabling high-fidelity FM stereo radio transmission when paired...
Electronic FM Telephone Transmitter Schematic. The following schematic design illustrates a circuit diagram for an FM telephone transmitter built on a compact PC board layout. This small design allows it to be easily integrated within the housing of a telephone,...
A Phase Locked Loop (PLL) can be utilized to create a Frequency Modulation (FM) demodulator. The PLL circuit tracks the input frequency by adjusting the voltage input of a Voltage-Controlled Oscillator (VCO).
The Phase Locked Loop (PLL) is a critical component...
A simple FM transmitter utilizing a single transistor. Mini FM transmitters are commonly regarded as one of the fundamental circuit types for beginners in amateur electronics. When constructed correctly, they offer clear wireless sound transmission via a standard FM radio...
Maxim has introduced a series of five integrated oscillator building blocks in the MAX260x series, covering a frequency range of 45 to 650 MHz. The MAX2606 is designed for the VHF band, allowing frequency variation of approximately ±3 MHz around...
This is a compact yet powerful FM transmitter featuring three RF stages and an audio preamplifier for enhanced modulation. It delivers an output power of 4 Watts and operates on 12-18 VDC, making it highly portable. This project is ideal...
The AN7158N is an integrated circuit designed for a power amplifier with an output of 7.5W (16V, 4Ω) that features low noise and low distortion. It is suitable for use in television sets with multi-sound capabilities. The design incorporates two...
The car MP3 FM transmitter circuit is designed to broadcast audio signals to FM receivers. It incorporates a high-quality preamplifier circuit, ensuring that the sound quality of the broadcast is excellent.
The car MP3 FM transmitter circuit typically consists of several...
This FM spy telephone circuit is connected in series with the phone line. When there is a signal on the wires, this transmitter will radiate airwaves through the wires, which act as an antenna. There is no need for batteries...
We use cookies to enhance your experience, analyze traffic, and (if you allow) serve personalized ads.
By clicking Accept All, you agree to our use of cookies.
Learn more