Experiments Included:

  • Main characteristics of an FM transmission system
  • Detuned resonant demodulator
  • Quadrature demodulator
  • Phase Locked Loop demodulator
  • Foster-Seeley/Ratio Detector demodulators
  • FM Radio Ratio Detector
  • Static Measurements
  • Dynamic Measurements
  • Ratio Detector Alignment
  • Second FM IF Amplifier
  • First FM IF Amplifier
  • FM RF Amplifier, Mixer, Oscillator, And AFC Stage
  • FM Mixer Static Measurements
  • FM Mixer Dynamic Measurements
  • FM Oscillator Static Measurements
  • FM AFC
  • FM RF Amplifier Measurement
  • FM Final Alignment

IT-4109 is designed to analyze the Techniques of Frequency De-Modulation using Analog signals. Trainer also contains an FM Radio Receiver with AFC. Frequency demodulators are also included to study the wired Frequency De-modulation techniques.


  • Power Supply Included
  • Required Circuits Tested
  • Each Section Clearly Marked for Input and Output
  • Each Section Works as an Independent Unit
  • Input Devices like Antenna and RF Amplifier Included
  • Output Devices like Speaker and Low Pass Filter Included
  • Complete FM Radio Receiver Included
  • FM Demodulation Techniques Explored

Technical Features:

FM Demodulator Types:

  • Detuned Resonant
  • Quadrature Detector
  • Foster -Seeley
  • Ratio – Detector
  • Phase Locked Loop
  • FM Radio
  • Carrier Frequency: 455 KHz
  • Low Pass Filter: 5th Order Butterworth @ 3.4 KHz
  • Amplifier: AC Amplifier with adjustable gain
  • Audio Amplifier: Monolithic Type
  • Speaker: 8 Ohm with ON/OFF Control

FM Radio

  • Sensitivity: <150mV
  • FM Tuning Range: 88-108MHz
  • FM IF: 10.7MHz
  • Detector: Ratio Detector
  • IF Amplifier 1: First FM IF Amplifier
  • IF Amplifier 2: Second FM IF Amplifier
  • Oscillator: FM Oscillator with mixer
  • Amplifier: FM RF Amplifier with AFC Stage
  • Antenna: FM Telescopic Antenna
  • Gang: AM/FM Gang for Tuning
  • Interconnections: 2 mm gold plated pins

Accessories: Power cord, Experiment Manual, Set of 2mm patch cords