❒112. Install C2, 100 to 220 uf electrolytic capacitor. Be sure to observe polarity - especially with this part since it is directly across the power supply and if reversed, could overheat so fast, so much that it could explode!

❒113. Install D5, 1N4002 style black epoxy diode, observe correct orientation of the banded end.

❒114. Install D2, 1N4148 style signal diode (glass body with black band). Observe correct orientation of the banded end.

❒115. Locate the aluminum press on heat sink and slip it on to Q6.

❒116. Install the LED transmit

indicator, LED1. Correctly identify the

 

Short lead here

cathode side lead which is the

 

Leave leads long R13

 

shorter of the two. The shorter lead

 

 

 

 

goes into the hole nearest R13.

Install the LED, leaving full lead length extending above the board so that the LED can be positioned later into the front panel indicator hole.

❒117. Install a wire jumper between points A and C on the PC board. This allows the use of an Icom/Yaesu/Radio Shack microphone plugged into jack J2.

This completes our assembly of the FT146 two meter FM transmitter. Now's a good time to give your masterpiece a good going over, being especially alert for any:

•bridged over solder joints,

•misplaced components,

•transistors or diodes placed incorrectly,

•electrolytic capacitors installed incorrectly.

TESTING, ALIGNMENT AND ADJUSTMENT

To prepare your FT146 for testing, you'll need the following items:

❒1. A suitable microphone of the Icom, Yaesu or Radio Shack variety. Other microphones may be used providing you mate them correctly to the FT146. Since there are such a wide variety of microphone types and styles, we cannot provide exact hook-up wiring for every case. Hook-up is very simple, follow the basic instructions in the "Microphone Considerations" section.

❒2. A hexagonal, non-metallic alignment tool. If you do not already have a set of plastic or nylon coil alignment tools and do expect to build more ham radio or electronic hobby projects, such tools are worth having and can be found inexpensively at any electronics store including Radio Shack. While a metal Hex key wrench will fit the coil slug, the metal itself will detune the

FT146 • 18

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Ramsey Electronics FT146 manual Short lead here, TESTING, Alignment and Adjustment
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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.
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