Using a 4046 PLL this circuit recognizes a 1.6 to 1.8 kHz tone by driving an output LED. The circuit is from a Radio Electronics from December 1989.
Using a 4046 PLL this circuit recognizes a 1.6 to 1.8 kHz tone by driving an output LED. The...
This multiple cable test sequential circuit was found in Radio Electronics. The connector must be...
This is the traditional configuration of a high-pass filter with an operational amplifier, such as...