There are many ways to filter the hum noise from AC line (50 Hz) from audio signal away. This is Hum Filter circuit using electronic coil. A frequency filter usage…
High quality, 3A adjustable voltage regulator. Using LM317 and 2N3055 so easy and cheap. Adjust voltage in steps 3V, 6V, 9V, 12V. And In fine, 1.25V to 20V.
This is a 0-60V, Dual Variable power supply circuit using LM317 and LM337 at 1.5A current so can builds to easy with PCB layout, adjustable voltage VR1,VR2 [...]
The experiment on the simple series circuit. To understand current flow and voltage across all devices in the circuit.
For digital that need high current 5A up it low noise and easy to build because is linear
