space for several different FM stations, this is a "generous" limitation designed to accommodate cruder FM devices. Properly built and adjusted, the FM10A kit operates well within this limit. In fact, its signal should sound no "wider" than any other FM station when listening on an ordinary FM radio.

c. FCC Rule 15.215(a) says: "Unless otherwise stated, there are no restrictions as to the types of operations permitted under these sections." This general provision appears to leave you free to use your FM stereo transmitter in a manner similar to operations of an FM broadcasting station, or to use it for any other non-interfering, practical application.

d. FCC Rule 15.5: General conditions of operation: "(b) Operation...is subject to the conditions that no harmful interference is caused and that interference must be accepted that may be caused by the operation of an authorized radio station, by another intentional or unintentional radiator, by industrial, scientific and medical equipment, or by an incidental radiator. (c) The operator of a radio frequency device shall be required to cease operating the device upon notification by a Commission representative that the device is causing harmful interference."

e. The most specific FCC regulation of 88-108 MHz FM Broadcast band unlicensed operation is that the "field strength" of the signal must not exceed 250 microvolts/meter at a distance of 3 meters from the transmitter (FCC rule 15.239). If you have any concern about this emission limit, have your device checked by a technician with accurate measuring equipment. Remember that the "field strength" of a signal is determined as much by the antenna as by the RF output of the transmitter itself.

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Ramsey Electronics FM10A manual

FM10A specifications

The Ramsey Electronics FM10A is a compact and efficient FM transmitter tailored for hobbyists, educators, and anyone with a passion for creating their own radio broadcast. This device stands out in the world of electronics due to its user-friendly design and array of features that make it an ideal starting point for both beginners and experienced users.

One of the main characteristics of the FM10A is its simplicity in setup and operation. Users can quickly assemble the kit without the need for advanced soldering skills, making it accessible to a broader audience. The transmitter operates in the FM band, allowing for high-quality broadcasts with minimal distortion. Its frequency stability is maintained through a PLL (Phase-Locked Loop) technology, ensuring that the transmitted frequency remains consistent throughout its operation.

The FM10A features adjustable transmission power, allowing users to customize their broadcast range. With a maximum range of approximately one mile under optimal conditions, this device is versatile enough for personal use, small events, or classroom demonstrations. Additionally, the transmitter is equipped with an audio input for connecting various media sources such as smartphones, computers, or other audio devices. This flexibility makes it suitable for a range of applications, from playing music to broadcasting educational content.

Another notable feature is its compact design, which makes the FM10A easy to transport and set up in different locations. The device is powered by a standard 12V supply, which is widely available, making it convenient for users at home or on the go. The lightweight nature of the unit further enhances its portability, enabling users to take their radio broadcasts anywhere.

The FM10A also includes an LED power indicator and a built-in antenna for straightforward operation. Users can enhance their transmitting range by adding an external antenna, providing further customization based on specific needs. The kit comes with comprehensive instructions to guide even those new to radio transmission through each step of assembly and operation.

In addition to its engaging technical features, the FM10A serves as an educational tool. Users can learn about radio frequency technology, electromagnetic theories, and audio broadcasting principles, making it an excellent addition to any STEM program. Overall, the Ramsey Electronics FM10A is a stand-out choice for anyone looking to delve into the world of FM transmission with a robust, user-friendly device that doesn't compromise on quality and functionality.