Converting battery operated display to 240volt supply

[Over80]

I have three displays which we use at Christmas inside the house which are battery operated. Can I use a step down transformer connected to a timer so that the supply will switch on and off at set times. I would be converting from 240 volts ac to 5vol DC

 

[Geoff1946]

No reason why not. 5 volt plug in PSUs are common.  The only considerations are how to physically make the connections.

Be aware that many of the battery boxes used for led lights incorporate a resistor too.  That needs to remain in circuit so don't just cut the wire without checking.

I've done what you are trying to do, in the past, by cutting  pieces of dowel the size of an AA cell and putting a drawing pin or similar in the end with the wires attached.