Help with camera repair. [Dynax]

Hello, i recently got a Minolta/Dynax 500si from my dad, this camera hasnt been used in approx. 20 years but it was stored in good condition (without film or the battery inside).
I tried using a lab power supply because i couldnt find any batteries near me and the camera draws 0.044 A but it doesnt turn on.
Any suggestions?
Thanks.

I don't know but try to use the battery. I tried my camera with lab power supply and it didn't work either but did work with battery.

thanks for the answer, i will try.