Current shield RS232 (CB8075E)

Found in a Popular Electronics from the 9s, this circuit has output for RS-232 interfaces and current input. The power supply must be symmetrical.

| Clique na imagem para ampliar |

Positive Peak Detector (CB15310E)
Other operational amplifiers of the same series can be used on this circuit found in Motorola's Linear...
1 second flash (CB22199E)
Found in 1980s documentation, this circuit produces 1 Hz flashes. The op amp supports equivalent. R5...
Dual Tuning Circuit with Varicap (CB13344E)
In the figure we have the way to use a single control voltage to act on two varicaps...