Here I am making a Ni-MH battery charger which works from AC 230v. It is a SMPS base circuit. SMPS is a better alternative for the transformer based power supply. Here I designed a simple SMPS circuit based on a single transistor. The transistor is act as the oscillator and also as the driver. This simple SMPS provide sufficient voltage for the battery charging and also there is a full charge indication LED.For the complete making process visit my Instructable,
https://www.instructables.com/id/Ni-MH-Battery-Charger/

For more circuit details visit my BLOG. Link given below,
https://0creativeengineering0.blogspot.com/2018/12/ni-mh-battery-charger-for-230v.html