Documentation.docx

COLLEGE OF ENGINEERING AND INFORMATION TECHNOLOGY

FM Transmitter Project in ECE 111

Submitted by: Panamogan, Hannie Redoble, Alfred Tamayo, Frank Kinneth Yee, Ryan Glenn Submitted to: Engr. Thesa L. Vergara

I.

Introduction:

Unless the message arriving from the information source is electrical in nature, it will be unsuitable for immediate transmission. Even then, a lot of work must be done to make such a message suitable. Transmitter is an electronic device which produces radio waves with an antenna. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating current, the antenna radiates radio waves; where it is necessary to convert the incoming sound signals into electrical variations, to restrict the range of the audio frequencies and then to compress their amplitude range. All this is done before any modulation. In wire telephony no processing may be required, but in long-distance communications, a transmitter is required to process, and possibly encode, the incoming information so as to make it suitable for transmission and subsequent reception. Eventually, in a transmitter, the information modulates the carrier, for example, is superimposed on a high-frequency sine wave. The actual method of modulation varies from one system to another. Modulation may be high level or low level, and the system itself may be amplitude modulation, frequency modulation, pulse modulation or variation or combination of these, depending on the requirements. The term transmitter is usually limited to equipment that generates radio waves for communication purposes; or radiolocation, such as radar and navigational transmitters. Generators of radio waves for heating or industrial purposes, such as microwave ovens or diathermy equipment, are not usually called transmitters, even though they often have similar circuits.

II.

Materials C2655 Transmitter 1 watt 100ohm resistor 1 watt 4.7Kohm resistor 47pF capacitor 102pF capacitor Electric Mic PCB Board #18 solid wire (coil) 9v Battery

1 pc 1 pc 1 pc 1 pc 1 pc 1 pc 2”x2” About 6 inches 1 pc

III.

Procedures

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IV.

Prepare the materials needed. Place the components on the breadboard for testing, follow the diagram given. For the coil, use the #18 magnetic wire to form the coil, we used a ¼” bolt to form the coil. When attaching the electric mic, make sure to follow the proper polarity of the leads. Check the connections before attaching the supply voltage. Test the transmitter using any FM receiver. We used a mobile phone as a receiver, search the frequencies for your transmitter Design the case so that it appears pleasing to the eyes. Once the transmitter is working, you can transfer the components to the PCB and solder them together. Place the PCB in a case that will hold it securely and will protect it. Test the final transmitter again.

Diagram

V.

Final Output

VI.

Conclusion

Having been challenged by our instructor to deal with transmitters is such a wondrous opportunity for us to be able to know how AM and FM Radios work.It helps us to better understand the characteristics of such component and how it plays an important role in field of communication, particularly, in radios. Unfortunately, we find it hard to have a better result since we use a microphone component for which it is prone to any information that is unwanted. It affects the output of a receiver. The carrier and noise voltages will mix, and if the difference is audible, it will naturally interfere with the reception of wanted signals. So, we recommend replacing the said component for the better information we wish. Indeed, dealing with transmitters is one of the interesting activities students might have. It requires patience, teamwork and camaraderie in order to meet desired results. However, the lack of this resorts to unavailability of the transmitters to transmit better signal to the receiver. And that's the very mere reason why information is susceptible to distortion.