Ramsey Electronics FT146 manual

❒21. Install R15, 10K ohm (brown-black-orange).

❒22. Install C33, .001 uf disc capacitor (marked .001, 1 nf or 102).

❒23. Install R16, 10K ohm, (brown-black-orange).

Time for a breather and progress check. So far, we've built up the audio section of our transmitter, from microphone amplifier to low pass filter to buffer stage - not bad for less than an hour! Give a quick check to see that you've installed all parts in the correct places and that all joints are soldered nicely with no splashes or bridges.

❒24. Install R24, 2.2K ohm (red-red-red).

❒25. Install R23, 10K ohm (brown-black-orange).

❒26. Identify Q7, a 2N3906 PNP transistor (marked 221334). Do not confuse it with the other transistors in your kit. Position Q7's large flat side as shown in the parts layout diagram. Press the transistor snugly into the PC board so that only a minimum amount of wire lead is exposed above the board. In soldering, do not be afraid of using enough heat to make a good solid connection.

❒27. Install R21, 2.2K ohm (red-red-red).

❒28. Install C45, .001 uf (marked .001, 1 nf or 102).

❒29. Install R25, 470 ohm (yellow-violet-brown).

❒30. Install R11, 1K ohm (brown-black-red).

❒31. Install R27, 10K ohm (brown-black-orange).

❒32. Install R12, 10K ohm (brown-black-orange).

❒33. Install D1, BB609 varactor diode (small black body with yellow band). Varactor diodes act as voltage variable capacitors. In his case, D1's capacitance is varied by the amplified voltage from your microphone, causing the crystal oscillator's frequency to change - in exact step with your voice. Voila, FM or Frequency Modulation!

❒34. Install C35, .01 uf (marked .01 or 103 or 10 nf).

❒35. Install C32, .001 uf disc capacitor (marked .001, 1 nf or 102).

❒36. Install R26, 10K ohm (brown-black-orange).

❒37. Install R5, 47K ohm (yellow-violet-orange).

❒38. Install C24, 100 pf disc capacitor (marked 100 or 101).

❒39. Install C30, 470 pf disc capacitor (marked 470 or 471).

❒40. Install R8, 270 ohm (red-violet-brown).

FT146 • 10

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.