100 Hz Second Order High Pass Filter (CB25815E)

This filter with the 741 op amp was found in the February 1995 Electronics Now magazine. The power supply must be dual.

Stereo Amplifier (CB20633E)
This amplifier with gain control was obtained in a documentation from Signetics of the 80's....
Two Transistors MW Receiver (CB18439E)
The commercial MT2B receiver manufactured in Japan in the 1960s had a listening device only and...
Ion generator (CB7837E)
This negative ion generator was found in a 90s Popular Electronics. The autotransformer can be an...