The equipment produces amplitude modulation of an internally generated RF carrier by an external audio signal or a locally available DC signal. Demodulation can be done by two different types of detectors.
Modulator Carrier Freq : 100KHz
Oscillator : Built-in.
Types of Amp. : 1.DSB with Carrier Modulation
2.DSBS ( Supressed Carrier )
T ypes of Detector : 1. Diode Type w/ Variable RC (1mS- 10mS)
2. Product / Square Law detector, local freq. 500 KHz.
Local oscillator : Can be locked in phase or can run out of lock w.r.t 500 KHz Carrier Osc.
Spectrum Analyser : Built-in for measurement & detection of sidebands in the modulated signal.
Study of slope distortion caused by excessive time constant in detector circuit.
Measurements of sidebands present in the modulated signal by spectrum analyser.
Changing the time constant of the detector circuit and seeing its effect on Modulation.
Economy Model : Amplitude Mod. /Demod. without Product Detector & Spectrum Analyser.