1-Ttube reflex receiver (T1555E)

This one-tube circuit is equivalent to the previous one. We find it in a 1924 book by Gernsback, Power is made by batteries.

Phase shift oscillator (CB20438E)
This circuit has a common configuration widely used in projects on this site. The transistor is...
Handbook of Electronics Formulas and Calculations - Volume 1
Author: Newton C. Braga Published:Aug, 2016 Formato:Book and e-Book Pages:...
Locking Touch Switch (CB1523E)
We find this circuit in an American publication of 1978. The integrated circuit is the CMOS 4013...