Circuit knowledge

There are two signals that are directed at the so-called FM transmitterthe coder (coding). Multiplexing Mpx signal has been contained, two left signals and right indirectly. Frequency modulation of a transmitter carried by the signal Mpx. The receiver output signal is obtained on Mpx and FM detector is then passed to the decoder. At the decoder do the opposite with the coder in the transmitter, because at this level produced two signals L and D.

Signal is amplified by audio amplifier dientik two, then reproduced through two speakers are the same. Now listeners can heard coming from the left half the loudspeaker is placed on the left and right half of which is placed on the right side. Situation amid the orchestra will be equal to that of the second lordspeaker reproduced, made ​​an impression on the listener as if there.

The third loudspeaker placed midway between the left and right. Based on all these listeners have a picture of the layout space, which is significantly increased total musical impression. Electronic circuits of the portable stereophonic radio receiver with headphones reproduction, made ​​by the IC TDA 7088T is shown in Figure the above. This is a practical embodiment of the receiver with TDA7040T decoder and two audio amplifier with TDA7050T IC.

Choke (coils) L3, L4 and L5 are HF coil allows the headphone cable is used as a receiving antenna. this fulfilled by connecting one contact of the plug-in headphones, through a 10 pF capacitor at the point where the output of the antenna is connected. Coil has a significant barrier to the signal station, preventing ground connection through capacitor 47 mF or through the TDA7050T output.