Audio Kits
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 + [...]
Electronic Metronome circuit schematic
This metronome schematic is not modern but is cheap and reliable. The well known 555 is presented in this metronome circuit and produces regulated impulses wich can be heard at a speaker. The metronome frequency can be adjusted with P1. The power supply is a 9V battery and if you use a 8Ω speaker insert [...]
