Scale Expander for 12V Meter (CB21330E)

This circuit was found in a QST from the 1990s. The circuit expands the scale of a 10V instrument to measure 20V.

Astable 4001 (CB12721E)
The circuit shown in the figure generates a rectangular signal whose frequency depends on C1. For...
Pulse Amplifier Shield (CB16019E)
This circuit suggested by Texas Instruments, operates with pulses, and is based on an operational...
Wireless Headset (CB16745E)
This circuit captures, through a coil, the signals emitted by another coil under the mat connected to...