Looks like it is transitioning in the linear region. Transistor will get
hot before the relay closes, unless the light transition is steeper.
Maybe a zener in the base circuit will help, or add another transistor
and make a schmidt trigger.
Rick

Roman Black wrote:

> Eke Neehr wrote:
> >
> > Sorry for the wrong format before
> > but here I4m attaching a shema in .GIF
> > format on a circuit I have some problem with.
> > The relay don4t switch over directly without
> > stands and vibrations before it changed.
> > What is wrong?
>
> >                               Name: Norp12.gif
> >                Part 1.2       Type: GIF Image (image/gif)
> >                           Encoding: base64
>
> Thanks for using a standard format now. :o)
> Try adding a 1uF capacitor between base and
> emitter of the transistor, and maybe another
> one across the 2 lower resistors.
> -Roman
>
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