AF amplifier and modulator using the TDA2003
The TDA2003 is suitable as an audio part for radio receivers and stereos. The reachable output power is 10 watts. It achieves a good reproduction quality. One finds the TDA2003 but also as an audio component in transceivers. In the arrangement shown, the power is limited to about 1 watt. In addition, the value of the electrolytic capacitor at the output reduces the frequency range downwards. For good intelligible voice reception, the lower frequency components do not have to be transfered.
Too efficiently transfer of the highs, on the other hand, allows noise to come to the fore in reception. For this reason, and in context to the reduced lower frequency components, to achieve a balanced sound for voice radio applications the connected demodulator should be provided with a low-pass filter.
The advantage of the TDA2003 is the small housing and the extremely simple connection scheme with only five pins.