In the figure we have the way to use the transistors of an old-paired pair as a trigger circuit. The circuit is by Philips from an old documentation.
This 10 mA microammeter circuit can measure currents of 50 uA. The circuit is from a publication from the...
This circuit charges a battery to power a flashlight at night. The circuit is from an English...
We found this transistor siren in an old English publication. The transistors are from the era,...