Pentode Mixer (T295E)

This circuit is from 1964 documentation. Its purpose is to mix RF signals to obtain the beat frequency in communications applications.

Frequency Doubler (CB4869E)
This low-frequency circuit for alternating signals is from an early American 1980s documentation. The...
Visual Modulation Monitor (CB5354E)
R1 may be 10k and R2 100k. The transistor can be the BC548 and instead of the small lamp we can...
TVS912A Texas Instruments General Purpose Operational Amplifier
Featuring an 8 MHz passband, Texas Instruments TVS912A operational amplifiers can be found at...