This simple power supply, which is equivalent to 2 AAA or AA batteries, was found in an Elektor from the 90's. The transformer has a 4.5 V secondary with a current of 50 mA or more.
January 2017 - The new Honeywell RSC TruStability ™ pressure sensor mounting board is available from...
With the appropriate choice of C1 and C2 it is possible to divide the frequency of a rectangular 3 V...
This circuit was obtained from an American publication from the 80's. We can use a BD136 instead...