Audio Kits
Automatic Gain Control - AGC
Automatic Gain Control or AGC is a circuit design which maintain the same level of amplification for sound or radio frequency. If the signal is too low the AGC circuit will increase ( amplify ) the level and if is to high will lower it to maintain a constant level as possible.
The Automatic Gain Control [...]
Voice, sound recorder circuit schematic
ISD1012, ISD1016 and ISD1020 are produced by ISD and allow sound voice recording and play-back. The last 2 digits show the maximum legth of recording time in seconds. This circuits contains a non-volatile memory which can memorise sound or voice without power supply up to 10 years. The circuit contains a microphone amplifier and a [...]
Audio compressor
This is a dynamic audio compressor which output a constant audio level and can be used for transmitters. It uses a preamplifier with TDA 1054 produced by SGS-ATES. IC1a is a preamplifier stage with a total gain of 50 (1 + R5/R4). IC1b is connected as a amplifier stage with a 400x gain (1 + [...]
