4. MC3359 FM IC and ASSOCIATED COMPONENTS

55. Install R17, 10K ohms [brown-black-orange]

56. Install R14, 33K ohms [orange-orange-orange]

57. Install C24, .001 uF [marked .001, 102, or 1 nF].

58. Install C25, .001 uF [marked .001, 102, or 1 nF].

59. Install C26, .01 uF [marked .01, 103, 10 nF].

60. Install L4, the 455 KHz quadrature coil [marked LB53303], soldering the two pins and the two mounting tabs.

61. Install MC3359 IC, U2. As in the case of the SA602 IC, you could choose to install an 18-pin IC socket rather than soldering the IC directly. Re-read the discussion of IC sockets offered for the installation of U1. Larger IC's such as the MC3359 require considerably more care in socket insertion. Notice that the end of the IC marked by a band, dot, or notch must be oriented correctly as shown on the parts layout diagram. Solder each of the 18 connections carefully. Make sure you have good lighting as well as good technique to make sure that no solder "bridges" flow between the connections.

62. Install C22, 100 pF (marked 100, 101, or 101K).

63. Install C16, .01 uF [marked .01 or 103 or 10 nF].

64. Install C17, .01 uF [marked .01 or 103 or 10 nF].

65. Install C21, .01 uF [marked .01 or 103 or 10 nF].

66. Install C18, 220 pF [marked 220 or 221].

67. Install C19, 22 pF.

68. Install Y1, the 10.24 MHz. crystal. No special procedure is required. Simply press the crystal firmly into its holes as far as it will go, and make good solder connections.

69. Install FL2, the 450 KHz filter. Its three leads are delicate and fit in only one way.

70. Install C23, .001 uF [marked .001, 102, or 1 nF].

71. Install C27, 1 uF electrolytic, observe correct polarity.

72. Install D2, the 1N4148 signal diode, observe correct orientation of the banded cathode end. Be sure you correctly identified D2 and did not confuse it with the varactor diode already installed.

FR146 • 16

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Ramsey Electronics FR146 manual MC3359 FM IC and Associated Components

FR146 specifications

The Ramsey Electronics FR146 is a versatile RF transmitter that has gained popularity among hobbyists and professionals alike for its reliability and performance. This compact and efficient device operates in the 146 MHz frequency range, making it suitable for various applications, including remote control systems, wireless audio, and telemetry. Its lightweight design and user-friendly interface make it an excellent choice for both beginners and seasoned RF enthusiasts.

One of the standout features of the FR146 is its ability to deliver a stable and clean signal. It employs advanced modulation techniques to ensure high-quality transmissions, minimizing interference and distortion. The device supports AM modulation, which is ideal for long-range communication due to its excellent propagation characteristics. This feature is particularly useful in outdoor environments where signals can travel considerable distances.

Another significant advantage of the FR146 is its user-adjustable output power. Users can easily modify the transmitter's power settings to suit specific needs, whether they require low power for short-range applications or higher power for extended reach. This flexibility allows for greater versatility in operation and makes it suitable for various scenarios.

The FR146 also comes equipped with a built-in tone generator, which can be used to encode audio signals. This feature allows for the integration of sound with the RF transmission, making it a perfect choice for projects that require audio broadcasting. Furthermore, the device includes a frequency stabilization circuit, ensuring that the transmitter maintains a consistent frequency even under varying temperature and voltage conditions.

In terms of construction, the FR146 is designed for durability and ease of use. It features a robust enclosure that protects the internal components from environmental factors. The device is straightforward to set up, often requiring only a few simple connections for operation. Its lightweight design enables easy mobility, making it suitable for portable applications.

Overall, the Ramsey Electronics FR146 stands out for its combination of advanced features, robust performance, and ease of use. Whether you are working on a personal project, conducting experiments, or managing professional tasks, the FR146 offers a reliable and effective solution for your RF transmission needs. Its adaptability across different applications makes it a valuable addition to any electronics enthusiast's toolkit.