Inductors and ferrite cores:

2 Shielded can tunable inductor (marked 007007) [L9,13]

2 Tunable inductor (pink plastic body) [L5,11]

2 6 hole ferrite bead core [L1,6]

2 Small ferrite bead core [L10,12]

2 Aluminum coil shield cans [for L5,11]

Semiconductor devices:

1 1N4002 style black epoxy diode [D5]

2 1N4148 style signal diode (glass body with black band) [D2,4]

1 BB609 varactor diode (black body with yellow color band) [D1]

1 Zener diode, 6.2 volt (gray body with black band) [D3]

2 2N3904 NPN transistor (marked 2N3904) [Q1,2]

1 2SC2498 or 2SC2570A VHF/UHF NPN transistor (marked C2498 or 2570A) [Q3]

1 NE021 flat pack NPN transistor (marked 021) [Q4]

1 2N3866 metal can NPN transistor [Q5]

1 SD1127 metal can RF power transistor [Q6]

1 2N3906 style PNP transistor (marked 221334) [Q7]

1 LM358 dual op-amp IC chip [U1]

1 LED Light emitting diode [LED1]

Special components:

1 Crystal 16.280 MHz (for 146.520 MHz output) [Y1]

1 5 pin DIN connector [P1]

1 RCA style phono jack [J1]

1 2.5MM sub-miniature phono jack [J2]

1 Push-on aluminum heat sink

1 5/16" x 20 bolt (to wind coils on)

1 1/2 feet enameled magnet wire

1 1/2 feet tinned buss wire

Required, not supplied:

12 volt DC power source at 1 amp minimum

Microphone

Dummy load or suitable antenna

Enclosure such as the Ramsey CFT

FT146 • 7

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Ramsey Electronics FT146 Inductors and ferrite cores, Semiconductor devices, Special components, Required, not supplied

FT146 specifications

The Ramsey Electronics FT146 is a versatile and compact FM transmitter that stands out for its user-friendly operation and impressive performance in both amateur and professional audio applications. Designed for hobbyists, educators, and small businesses alike, the FT146 offers a reliable solution for broadcasting audio signals over a short to moderate range.

One of the main features of the FT146 is its simple plug-and-play setup, which allows users to get started quickly without needing extensive technical knowledge. The device operates with a frequency range of 88.1 to 107.9 MHz, covering the entire FM broadcast band. This flexibility enables users to choose the best frequency for minimal interference in their transmission area. Additionally, with an adjustable output power of up to 2 watts, the FT146 can effectively cover distances ranging from a few hundred feet to several miles, making it ideal for a variety of broadcasting scenarios.

The FT146 utilizes advanced modulation technology to ensure high-quality audio transmission. It supports monophonic audio, which is perfect for clear voice and music transmission. The integrated audio limiter prevents distortion, ensuring that the sound quality remains consistent, even at higher volumes or varying audio signals.

Another notable characteristic of the FT146 is its robust construction. Housed in a durable metal enclosure, the transmitter is built to withstand everyday use. The compact design allows for easy portability, making it suitable for field applications, on-location broadcasting, or as a permanent installation in a small venue.

In terms of connectivity, the FT146 features multiple audio input options, including a 3.5mm jack and RCA inputs. This versatility allows users to connect various audio sources, such as MP3 players, computers, or professional-grade audio equipment.

Furthermore, the FT146 also includes an LED power indicator and a built-in antenna output for enhanced transmission efficiency. Users can either connect an external antenna for increased range or utilize the included telescopic antenna for convenience.

Overall, the Ramsey Electronics FT146 combines ease of use with professional-grade features, making it an excellent choice for anyone looking to explore FM broadcasting. Whether for personal projects, educational purposes, or small business promotions, the FT146 delivers reliable performance and adaptability in a compact package.