eloman
| | Tarih: 21.12.2006, 11:47 Mesaj konusu: FM Remote Speaker System | |
| INTRODUCTION
A high quality, noise free, wireless FM transmitter/receiver may be made using the LM566 VCO and LM565 PLL Detector.
The LM566 VCO is used to convert the program material into FM format, which is then transformer coupled to standard
power lines. At the receiver end the material is detected from the power lines and demodulated by the LM565.
The important difference between this carrier system and others is its excellent quality and freedom from noise.
Whereas the ordinary wireless intercom uses an AM carrier and exhibits a poor signal-to-noise ratio (S/N), the system
described here uses an FM carrier for inherent freedom from noise and a PLL detection system for additional noise
rejection.
The complete system is suitable for high-quality transmission of speech or music, and will operate from any AC outlet
anywhere on a one-acre homesite. Frequency response is 20±20,000 Hz and THD is under (/2% for speech and music
program material
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