Modulator for rectangular signals (CB21630E)

Based on TTL logic this circuit can vary both the frequency and the pulse width of a rectangular signal. Equivalent components can be tested.

| Clique na imagem para ampliar |

Scale Expander for Multimeter (CB10676E)
This circuit is from a Popular Electronics from April 1991. The magazine no longer exists, but the...
Fourth-order low-pass filter (CB25596E)
Using two 741 operational amplifiers, this low-pass circuit has a cutoff frequency of 10 kHz. We...
SCA signal decoder (CB9676E)
The SCA is a signal superimposed on the FM signals that make it possible to eliminate...