❒60. Install C21, 4.7 or 5 pf disc capacitor (marked 4.7 or 5 or 4.7K or 5K).

❒61. Install L9, slug tuned shielded coil (marked 007007). This coil is part of the first tripler section. It is tuned to the third harmonic of the crystal oscillator.

❒62. Install L13, another slug tuned shielded coil (marked 007007). This coil is also part of the first tripler section.

❒63. Install TP1. Select a 1K resistor, R9 (brown-black-red). Trim back one lead wire to a length of inch. Bend this wire into a small loop as shown. This loop will act as a convenient point to connect a test probe for tuning up your transmitter. Insert the resistor into the PC board and hold it carefully while you solder it to the board.

❒64. Install R6, 2 ohm resistor (red-black-gold).

❒65. Install C29, 100 pf disc capacitor (marked 100 or 101).

❒66. Install C22, 47 pf disc capacitor (marked 47 or 47K).

❒67. Locate Q4, NE021, the tiny black transistor disc stuck to a piece of paper (marked 021). Carefully remove it from its protective paper and bend all three leads down 90 degrees from its body. Notice how one lead is longer than the others, that lead (the collector) must be installed exactly as shown in the drawing - pointing towards L5. Set Q4 into the PC board

making sure that its body is snugly against the PC board and positioned

correctly. You should be able to read the

 

 

 

 

 

Test point loop

printed markings on the part, if you cannot,

Resisto

 

 

then you have the transistor flipped over.

r

PC board

 

 

Solder and trim all three leads.

 

 

 

 

 

 

 

❒68. Install R4, 1K ohm (brown-black-red).

❒69. Install C16, 100 pf disc capacitor (100 or 101).

❒70. Install C25, 12 pf disc capacitor (marked 12 or 12K).

❒71. Install L5, pink color slug tuned inductor. Make sure you place the coil body right up against the PC board snugly.

❒72. Install aluminum coil shield can cover over L5.

❒73. Install R10, 51 ohm (green-brown- black).

❒74. Install C31, .001 uf disc capacitor (marked .001 or 102).

Markings on this

side

This lead towards

L5

❒75. Install C17, 2 or 2.2 pf disc capacitor (marked 2 or 2.2).

Nine parts need handmade preparation before installation in the transmitter RF

FT146 • 12

Page 11 Page 13
Page 12
Image 12
Ramsey Electronics FT146 manual Test point loop, Resisto, PC board
Page 11 Page 13

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.
Top Page Image Contents