Help me to solve problem...

[TheHungry]

In one vire flow signal (see atteched JPEG) , some time first , some time second in graphics.
needed to convert this signal to TTL level .

Period of signal is 8ms.

please help me?

P.S
My english is very bad

 

[artem]

use npn transistor emitter connected to ground and base connected to signal input trhrough zener diod
for first case zener diod should have 1.5 V (or could be 2 Si diodes connected sequentially ) for the second
case 5 V zener diod will be enough . Use also resistor to reduce input current load connected sequentuially
with zener diod and another base-emitter resistor to prevent transistor from being opened due to zener diod impedance .

 

[TheHungry]

Schematic needed work with first and second signal without any change of component value.