2N4987 and 2N4990 (IP057E)

Unilateral switch (SUS) with 8 V of trigger voltage. This component is used to control SCRs and other applications.

Radiation Monitor (CB4561E)
This circuit was obtained from an 1974 Everyday Electronics magazine. The circuit is still current as...
Remote bell for telephone (CB5987E)
This circuit triggers a remote doorbell when the phone rings. The circuit is for the 110 V mains...
Monostable Using the 4098 (I) (CB137)
The 4098 IC contains two monostable multivibrators in the same package. The basic configuration...