Simple Circuit Schematic Television Transmitter with FM Audio Modulation and PAL Video Modulation

Eltronicschool. - This is one of Simple Circuit Schematic Television Transmitter with FM Audio Modulation and PAL Video Modulation like in Figure 1 below. In this circuit uses UK standard 1 FM modulation for sound and PAL for video modulation. 

Circuit schematic

Figure 1. Simple Circuit Schematic Television Transmitter with FM Audio Modulation and PAL Video Modulation (Source: Screenshot of Circuitstoday)

Component Parts

1. All components see in Figure 1 above

Description

Circuit schematic like in Figure 1 above is Simple Circuit Schematic Television Transmitter with FM Audio Modulation and PAL Video Modulation. According Circuitstoday site describe that the audio signal to be modulated is pre-amplified using the transistor Q1 and associated components. The transistor Q2 has two jobs: production of carrier frequency and modulation. The pre-amplified audio signal is fed to the base of transistor Q2 for modulation. Capacitor C5 and inductor L1 forms the tank circuit which is responsible for producing the carrier frequency. The video signal is fed to the emitter of transistor Q2 via POT R7 for modulation. The modulated composite signal (audio+video) is transmitted by the antenna A1. This TV transmitter circuit can be operated from 12V DC. Either a 12V DC power supply or a battery can be used for the purpose, using a battery will surely reduce noise and improve the performance. If you are going with a DC power supply, then it must be well regulated and free of  noise. Read more here.