This simple electronic music box circuit was found in the April 1985 issue of Radio Electronics. The components are common, and the note adjustments are made with trimpots.
The gain of the operational amplifier shown in the figure depends on the feedback resistor,...
June 2016 - It can be obtained from Mouser Electronics the new gate driver optocoupler from...
Figure shows the basic application of a data selector using the 4051 . The same configuration is...