Battery NiCad Charger which is bright

Intention from battery NiCad charger which is bright is to obviate mistake that is usualy is made man where often pairs battery by the way of wrong. At this scheme will refuse if installation of battery is not true. This scheme consisted of a source of current ( Q2 ) to take care of permanent output current 50 mA. Diode zener D2 and LED does bases Q2 at one particular constant level and thereby tension at R3 also constant, so long as condition of admission filling of NiCad at collector Q2 correctness.

Scheme protector consisted of Q1, D1 and R2. Terminal Voltage NiCad attached truly OFF will at Q1 causing prevents filler to operate. Directing to this thing will be given by Led, that is will not blaze. If battery is attached normally.