Audio Cable Tester (CB3827E)

This simple circuit tests both monophonic and other two-wire audio cables. The circuit is powered by two common batteries.

Logic Probe 7811 (CB19217E)
The integrated circuit used in this application is not very common. The circuit is intended for...
LM359 Fast Difference Amplifier (CB14374E)
The focused circuit was found in the National Semiconductor's Linear Applications Handbook of...
8W Amplifier Using the TDA2040 (CB443)
The TDA2040 is not a common IC these days, but if you find one you can build this high quality...