This FM transmitter for your stereo or any other amplifier provides a good signal strength up to a distance of 500 metres with a power output of about 200 mW. It works off a 9V battery.


The range of this FM transmitter is around 100 meters with a 9V DC supply


This FM transmitter circuit uses four radio frequency stages: a VHF oscillator built around transistor BF494 (T1), a preamplifier built around transistor BF200 (T2), a driver built around transistor 2N2219 (T3) and a power amplifier built around transistor 2N3866 (T4). A condenser microphone is connected at the input of the oscillator


This low-cost short-wave transmitter is tunable from 10 to 15 MHz with the help of ½ Jgang condenser VC1, which determines the carrier frequency of the transmitter in conjunction with inductor L1. The frequency trimming can be done with VC2. The carrier is amplified by transistor T4 and coupled to RF amplifier transistor T1 (BD677) through transformer X1*

Shortwave radio refers to the variety of radio frequencies normally among 1.6 and 30 MHz.
It is known as shortwave due to the fact the wavelengths used are shorter than those of the older, long-wave radio transmissions.

Shortwave radio alerts can tour long distances through bouncing off the Earth’s ionosphere, making an allowance for global communique. Unlike FM or AM radio, shortwave alerts can propagate over giant distances due to their potential to refract, or bend, off the ionosphere. This assets makes them perfect for long-range communication, mainly in remote areas or at some stage in emergencies when other varieties of communique may be disrupted. Shortwave radios are designed to obtain those alerts. They typically have a frequency tuning dial that allows customers to pick the preferred frequency in the shortwave range.

The radio’s antenna captures the radio waves, and the receiver converts them into audible sounds. Shortwave radio is used for numerous functions, which includes global broadcasting, maritime verbal exchange, beginner radio operations, and emergency communications. It has played a vital role in presenting information, facts, and entertainment to humans global, especially in regions with restrained get admission to to different forms of media. In latest years, advancements in virtual technology have allowed for the improvement of software program-defined radios which can decode virtual alerts on shortwave frequencies, opening up new possibilities for information transmission and reception.


Always know that disclaimer applies to this project because it is project that can cause radio frequency interference which can get you into a legal case

Daniel mayor
Hey i am daniel mayor, i am good @ electronics hardware circuitry and i also make electronics project during my free time. feel free to chat me up if you want a custom project or if learn more about electronics

Fm bug audio transmitter spy or Trojan device

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