Frequency Modulator/Demodulator with Spectrum Analyser
This module is designed to demonstrate the concepts involved in Frequency Modulation and Demodulation.
Types of Detector : 1.Diode Type with variable RC (1mS,10mS) 2.Product/Square Law detector; local freq 100KHz.
Local oscillator : Can be locked in phase or can run out of lock w.r.t. 100KHz
Modulators : 2 with built-in Carrier Oscillators
Carrier Oscillators : 2 Nos. having different frequencies
Signal I/P : AC modulating signals or local DC signal
Experiment on adjacent channel rejection : Can be performed as 2 modulators are given,serving as two transmitters
Types of detectors : 1. Foster Seeley Detector 2. Ratio Detector.
Spectrum Analyser : Given; Enables checking of various sidebands present in the modulated carrier.
Study of sidebands in FM signals as frequency is changed but magnitude is kept constant.
Study of sidebands with magnitude of modulating signal changing but frequency is kept constant.
Study ratio detector,Foster Seeley detector and their characteristics.
Observation of noise rejection of FM.
Economy Model : Freq. Modulator/Demodulator with only one Modulator & without Spectrum Analyser.