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[audioguru]

I am wondering why my transistor shows just 0.30V at CE while the base resistor is 100K ie collector resistor is 1/100 base resistor?

You cannot make a ratio of the collector resistor which has an LED in series with it and the base resistor that hase a base-emitter junction in series with it. Instead you must make the base current 1/20th of the collector current.
Your Vce is 0.39V which is not very low. It won't work with many BC108 transistors because the base current is too low (the value of the 100k base resistor is too high).

 

[Birdman Adam]

Flyback diode = Freewheeling diode.

Flyback Diode

 

[Electronman]

You cannot make a ratio of the collector resistor which has an LED in series with it and the base resistor that hase a base-emitter junction in series with it. Instead you must make the base current 1/20th of the collector current.
Your Vce is 0.39V which is not very low. It won't work with many BC108 transistors because the base current is too low (the value of the 100k base resistor is too high).

it is 0.33 when I put a 10k resistor instead of 100k!!!!!!!!!
you told me how to use 1/10 rule for saturation states and why you are telling that we can not make a ratio?
I used the 1/10 rule and took 0.33V for CE and I changed the value to 100k and now have 0.39V which is not so good I think. It seems to me that my transistor is in saturation yet because of VCE is equal to 0.39V

 

[audioguru]

I am used to American 2N3904 and 2N4401 transistors that have datasheets showing their max saturation voltage with the base current 1/10th the collector current.
The BC107, BC108 and BC547 European transistors have 1/20th on their datasheets.

The BC108 has a max saturation voltage of 0.25V when the collector current is 10mA like yours and a base current of 0.5mA. Your base current is more than twice as high but your saturation voltage is higher than it should be so your transistor is damaged maybe by avalanche breakdown before.

 

[Electronman]

I am used to American 2N3904 and 2N4401 transistors that have datasheets showing their max saturation voltage with the base current 1/10th the collector current.
The BC107, BC108 and BC547 European transistors have 1/20th on their datasheets.

The BC108 has a max saturation voltage of 0.25V when the collector current is 10mA like yours and a base current of 0.5mA. Your base current is more than twice as high but your saturation voltage is higher than it should be so your transistor is damaged maybe by avalanche breakdown before.

Damaged in simulation!!?

 

[audioguru]

Damaged in simulation!!?

If you don't have real parts then your simulation program didn't read the datasheets.

 

[mbarazeen]

just eliminate any resistance and use only the motor between C&E, use a diode as in relay switching for protection in worsecase.